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															SUPREME COURT OF THE UNITED STATES

															_________________

															No. 10–8505

															_________________

															SANDY WILLIAMS, PETITIONER v. ILLINOIS

															on writ of certiorari to the supreme court of
illinois

															[June 18, 2012]

															Justice Alito announced the judgment of the
Court and delivered an opinion, in which The Chief Justice, Justice
Kennedy, and Justice Breyer join.

															In this case, we decide whether Crawford v.
Washington, 541 U.S.
36 , 50 (2004) , precludes an expert witness from testifying in
a manner that has long been allowed under the law of evidence.
Specifically, does Crawford bar an expert from expressing an
opinion based on facts about a case that have been made known to
the expert but about which the expert is not competent to testify?
We also decide whether Crawford substantially impedes the ability
of prosecutors to introduce DNA evidence and thus may effectively
relegate the prosecution in some cases to reliance on older, less
reliable forms of proof.

															In petitioner’s bench trial for rape, the
prosecution called an expert who testified that a DNA profile
produced by an outside laboratory, Cellmark, matched a profile
produced by the state police lab using a sample of petitioner’s
blood. On direct examination, the expert testified that Cellmark
was an accredited laboratory and that Cellmark provided the police
with a DNA profile. The expert also explained the notations on
documents admitted as business records, stating that, according to
the records, vaginal swabs taken from the victim were sent to and
received back from Cellmark. The expert made no other statement
that was offered for the purpose of identifying the sample of
biological material used in deriving the profile or for the purpose
of establishing how Cellmark handled or tested the sample. Nor did
the expert vouch for the accuracy of the profile that Cellmark
produced. Nevertheless, petitioner contends that the expert’s
testimony violated the Confrontation Clause as interpreted in
Crawford.

															Petitioner’s main argument is that the expert
went astray when she referred to the DNA profile provided by
Cellmark as having been produced from semen found on the victim’s
vaginal swabs. But both the Illinois Appellate Court and the
Illinois Supreme Court found that this statement was not admitted
for the truth of the matter asserted, and it is settled that the
Confrontation Clause does not bar the admission of such statements.
See id., at 59–60, n. 9 (citing Tennessee v. Street, 471
U.S. 409 (1985) ). For more than 200 years, the law of evidence
has permitted the sort of testimony that was given by the ex- pert
in this case. Under settled evidence law, an expert may express an
opinion that is based on facts that the expert assumes, but does
not know, to be true. It is then up to the party who calls the
expert to introduce other evidence establishing the facts assumed
by the expert. While it was once the practice for an expert who
based an opinion on assumed facts to testify in the form of an an-
swer to a hypothetical question, modern practice does not demand
this formality and, in appropriate cases, permits an expert to
explain the facts on which his or her opinion is based without
testifying to the truth of those facts. See Fed. Rule Evid. 703.
That is precisely what occurred in this case, and we should not
lightly “swee[p] away an accepted rule governing the admission of
scientific evidence.” Melendez-Diaz v. Massachusetts, 557
U.S. 305 , 330 (2009) (Kennedy, J., dissenting).

															We now conclude that this form of expert
testimony does not violate the Confrontation Clause because that
provision has no application to out-of-court statements that are
not offered to prove the truth of the matter asserted. When an
expert testifies for the prosecution in a criminal case, the
defendant has the opportunity to cross-examine the expert about any
statements that are offered for their truth. Out-of-court
statements that are related by the expert solely for the purpose of
explaining the assumptions on which that opinion rests are not
offered for their truth and thus fall outside the scope of the
Confrontation Clause. Applying this rule to the present case, we
conclude that the expert’s testimony did not violate the Sixth
Amendment.

															As a second, independent basis for our decision,
we also conclude that even if the report produced by Cellmark had
been admitted into evidence, there would have been no Confrontation
Clause violation. The Cellmark report is very different from the
sort of extrajudicial statements, such as affidavits, depositions,
prior testimony, and confessions, that the Confrontation Clause was
originally understood to reach. The report was produced before any
suspect was identified. The report was sought not for the purpose
of obtaining evidence to be used against petitioner, who was not
even under suspicion at the time, but for the purpose of finding a
rapist who was on the loose. And the profile that Cellmark provided
was not inherently inculpatory. On the contrary, a DNA profile is
evidence that tends to exculpate all but one of the more than 7
billion people in the world today. The use of DNA evidence to
exonerate persons who have been wrongfully accused or convicted is
well known. If DNA profiles could not be introduced without calling
the technicians who participated in the preparation of the profile,
economic pressures would encourage prosecutors to forgo DNA testing
and rely instead on older forms of evidence, such as eyewitness
identification, that are less reliable. See Perry v. New Hampshire,
565 U. S. ___ (2012). The Confrontation Clause does not
mandate such an undesirable development. This conclusion will not
prejudice any defendant who really wishes to probe the reliability
of the DNA testing done in a particular case because those who
participated in the testing may always be subpoenaed by the defense
and questioned at trial.

															I

															A

															On February 10, 2000, in Chicago, Illinois, a
young woman, L. J., was abducted while she was walking home
from work. The perpetrator forced her into his car and raped her,
then robbed her of her money and other personal items and pushed
her out into the street. L. J. ran home and reported the
attack to her mother, who called the police. An ambulance took
L. J. to the hospital, where doctors treated her wounds and
took a blood sample and vaginal swabs for a sexual-assault kit. A
Chicago Police detective collected the kit, labeled it with an
inventory number, and sent it under seal to the Illinois State
Police (ISP) lab.

															At the ISP lab, a forensic scientist received
the sealed kit. He conducted a chemical test that confirmed the
presence of semen on the vaginal swabs, and he then resealed the
kit and placed it in a secure evidence freezer.

															During the period in question, the ISP lab often
sent biological samples to Cellmark Diagnostics Laboratory in
Germantown, Maryland, for DNA testing. There was evidence that the
ISP lab sent L. J.’s vaginal swabs to Cellmark for testing and
that Cellmark sent back a report containing a male DNA profile
produced from semen taken from those swabs. At this time,
petitioner was not under suspicion for L. J.’s rape.

															Sandra Lambatos, a forensic specialist at the
ISP lab, conducted a computer search to see if the Cellmark profile
matched any of the entries in the state DNA database. The computer
showed a match to a profile produced by the lab from a sample of
petitioner’s blood that had been taken after he was arrested on
unrelated charges on August 3, 2000.

															On April 17, 2001, the police conducted a lineup
at which L. J. identified petitioner as her assailant.
Petitioner was then indicted for aggravated criminal sexual
assault, aggravated kidnaping, and aggravated robbery. In lieu of a
jury trial, petitioner chose to be tried before a state judge.

															B

															Petitioner’s bench trial began in April 2006.
In open court, L. J. again identified petitioner as her
attacker. The State also offered three expert forensic witnesses to
link petitioner to the crime through his DNA. First, Brian Hapack,
an ISP forensic scientist, testified that he had confirmed the
presence of semen on the vaginal swabs taken from L. J. by
performing an acid phosphatase test. After performing this test, he
testified, he resealed the evidence and left it in a secure freezer
at the ISP lab.

															Second, Karen Abbinanti, a state forensic
analyst, testified that she had used Polymerase Chain Reaction
(PCR) and Short Tandem Repeat (STR) techniques to develop a DNA
profile from a blood sample that had been drawn from petitioner
after he was arrested in August 2000. She also stated that she had
entered petitioner’s DNA profile into the state forensic
database.

															Third, the State offered Sandra Lambatos as an
expert witness in forensic biology and forensic DNA analysis. On
direct examination, Lambatos testified about the general process of
using the PCR and STR techniques to generate DNA profiles from
forensic samples such as blood and semen. She then described how
these DNA profiles could be matched to an individual based on the
individual’s unique genetic code. In making a comparison between
two DNA profiles, Lambatos stated, it is a “commonly accepted”
practice within the scientific community for “one DNA expert to
rely on the records of another DNA expert.” App. 51. Lambatos also
testified that Cellmark was an “accredited crime lab” and that, in
her experience, the ISP lab routinely sent evidence samples via
Federal Express to Cellmark for DNA testing in order to expedite
the testing process and to “reduce [the lab’s] backlog.” Id., at
49–50. To keep track of evidence samples and preserve the chain of
custody, Lambatos stated, she and other analysts relied on sealed
shipping containers and labeled shipping manifests, and she added
that experts in her field regularly relied on such protocols. Id.,
at 50–51.

															Lambatos was shown shipping manifests that were
admitted into evidence as business records, and she explained what
they indicated, namely, that the ISP lab had sent L. J.’s
vaginal swabs to Cellmark, and that Cellmark had sent them back,
along with a deduced male DNA profile. Id., at 52–55. The
prosecutor asked Lambatos whether there was “a computer match”
between “the male DNA profile found in semen from the vaginal swabs
of [L. J.]” and “[the] male DNA profile that had been
identified” from petitioner’s blood sample. Id., at 55.

															The defense attorney objected to this question
for “lack of foundation,” arguing that the prosecution had offered
“no evidence with regard to any testing that’s been done to
generate a DNA profile by another lab to be testified to by this
witness.” Ibid.

															The prosecutor responded: “I‘m not getting at
what another lab did.” Id., at 56. Rather, she said, she was simply
asking Lambatos about “her own testing based on [DNA] information”
that she had received from Cellmark. Ibid. The trial judge agreed,
noting, “If she says she didn’t do her own testing and she relied
on a test of another lab and she’s testifying to that, we will see
what she’s going to say.” Ibid.

															The prosecutor then proceeded, asking Lambatos,
“Did you compare the semen that had been identified by Brian Hapack
from the vaginal swabs of [L. J.] to the male DNA profile that
had been identified by Karen [Abbinanti] from the blood of
[petitioner]?” Ibid.

															Lambatos answered “Yes.” Ibid. Defense counsel
lodged an objection “to the form of the question,” but the trial
judge overruled it. Ibid. Lambatos then testified that, based on
her own comparison of the two DNA profiles, she “concluded that
[petitioner] cannot be excluded as a possible source of the semen
identified in the vaginal swabs,” and that the probability of the
profile’s appearing in the general population was “1 in 8.7
quadrillion black, 1 in 390 quadrillion white, or 1 in 109
quadrillion Hispanic unrelated individuals.” Id., at 57. Asked
whether she would “call this a match to [petitioner],” Lambatos
answered yes, again over defense counsel’s objection. Id., at
58.

															The Cellmark report itself was neither admitted
into evidence nor shown to the factfinder. Lambatos did not quote
or read from the report; nor did she identify it as the source of
any of the opinions she expressed.

															On cross-examination, Lambatos confirmed that
she did not conduct or observe any of the testing on the vaginal
swabs, and that her testimony relied on the DNA profile produced by
Cellmark. Id., at 59. She stated that she trusted Cellmark to do
reliable work because it was an accredited lab, but she admitted
she had not seen any of the calibrations or work that Cellmark had
done in deducing a male DNA profile from the vaginal swabs. Id., at
59–62.

															Asked whether the DNA sample might have been
degraded before Cellmark analyzed it, Lambatos answered that, while
degradation was technically possible, she strongly doubted it had
occurred in this case. She gave two reasons. First, the ISP lab
likely would have noticed the degradation before sending the
evidence off to Cell- mark. Second, and more important, Lambatos
also noted that the data making up the DNA profile would ex- hibit
certain telltale signs if it had been deduced from a degraded
sample: The visual representation of the DNA sequence would exhibit
“specific patterns” of degradation, and she “didn’t see any
evidence” of that from looking at the profile that Cellmark
produced. Id., at 81–82.

															When Lambatos finished testifying, the defense
moved to exclude her testimony “with regards to testing done by
[Cellmark]” based on the Confrontation Clause. Id., at 90. Defense
counsel argued that there was “no evidence with regards to
. . . any work done by [Cellmark] to justify testimony
coming into this case with regard to their analysis.” Ibid. Thus,
while defense counsel objected to and sought the exclusion of
Lambatos’ testimony insofar as it implicated events at the Cellmark
lab, defense counsel did not object to or move for the exclusion of
any other portion of Lambatos’ testimony, including statements
regarding the contents of the shipment sent to or received back
from Cellmark. See id., at 55, 56, 90. See also 385 Ill. App. 3d
359, 367–368, 895 N.E.2d 961, 968 (2008) (chain-of-custody argument
based on shipping manifests waived).

															The prosecution responded that petitioner’s
Confrontation Clause rights were satisfied because he had the
opportunity to cross-examine the expert who had testified that
there was a match between the DNA profiles produced by Cellmark and
Abbinanti. App. 91. Invoking Illinois Rule of Evidence 703, [ 1 ] the prosecutor argued that
an expert is allowed to disclose the facts on which the expert’s
opinion is based even if the expert is not competent to testify to
those underlying facts. She further argued that any deficiency in
the foundation for the expert’s opinion “[d]oesn’t go to the
admissibility of [that] testi- mony,” but instead “goes to the
weight of the testimony.” App. 91.

															The trial judge agreed with the prosecution and
stated that “the issue is . . . what weight do you
give the test, not do you exclude it.” Id., at 94. Accordingly, the
judge stated that he would not exclude Lambatos’ testimony, which
was “based on her own independent testing of the data received from
[Cellmark].” Id., at 94–95 (alteration in original).

															The trial court found petitioner guilty of the
charges against him. The state court of appeals affirmed in
relevant part, concluding that Lambatos’ testimony did not violate
petitioner’s confrontation rights because the Cell- mark report was
not offered into evidence to prove the truth of the matter it
asserted. See 385 Ill. App. 3d, at 369, 895
N. E. 2d, at 969–970 (“Cellmark’s report was not offered
for the truth of the matter asserted; rather, it was offered to
provide a basis for Lambatos’ opinion”) The Supreme Court of
Illinois also affirmed. 238 Ill. 2d 125, 939 N.E.2d 268 (2010).
Under state law, the court noted, the Cellmark report could not be
used as substantive evidence. When Lambatos referenced the report
during her direct examination, she did so “for the limited purpose
of explaining the basis for [her expert opinion],” not for the
purpose of showing “the truth of the matter asserted” by the
report. Id., at 150, 939 N. E. 2d, at 282. Thus, the report
was not used to establish its truth, but only “to show the
underlying facts and data Lambatos used before rendering an expert
opinion.” Id., at 145, 939 N. E. 2d, at 279.

															We granted certiorari. 564 U. S. ___
(2011).

															II

															A

															The Confrontation Clause of the Sixth
Amendment provides that, “[i]n all criminal prosecutions, the
accused shall enjoy the right . . . to be confronted with
the wit- nesses against him.” Before Crawford, this Court took the
view that the Confrontation Clause did not bar the admission of an
out-of-court statement that fell within a firmly rooted exception
to the hearsay rule, see Ohio v. Roberts, 448 U.S.
56 , 66 (1980) , but in Crawford, the Court adopted a
fundamentally new interpretation of the confronta- tion right,
holding that “[t]estimonial statements of witnesses absent from
trial [can be] admitted only where the declarant is unavailable,
and only where the defendant has had a prior opportunity to
cross-examine.” 541 U. S., at 59. Crawford has resulted in a
steady stream of new cases in this Court. See Bullcoming v. New
Mexico, 564 U. S. ___ (2011); Michigan v. Bryant, 562
U. S. ___ (2011); Melendez-Diaz, 557 U.S.
305 ; Giles v. California, 554 U.S.
353 (2008) ; Indiana v. Edwards, 554 U.S.
164 (2008) ; Davis v. Washington, 547
U.S. 813 (2006) .

															Two of these decisions involved scientific
reports. In Melendez-Diaz, the defendant was arrested and charged
with distributing and trafficking in cocaine. At trial, the
prosecution introduced bags of a white powdery substance that had
been found in the defendant’s possession. The trial court also
admitted into evidence three “certificates of analysis” from the
state forensic laboratory stating that the bags had been “examined
with the following results: The substance was found to contain:
Cocaine.” 557 U. S., at 308 (internal quotation marks
omitted).

															The Court held that the admission of these
certificates, which were executed under oath before a notary,
violated the Sixth Amendment. They were created for “the sole
purpose of providing evidence against a defendant,” id., at 323,
and were “ ‘quite plainly affidavits,’ ” id., at 330
(Thomas, J., concurring). The Court emphasized that the
introduction of the report to prove the nature of the substance
found in the defendant’s possession was tantamount to “live,
in-court testimony” on that critical fact and that the certificates
did “precisely what a witness does on direct examination.” Id., at
311 (internal quotation marks omitted). There was no doubt that the
certificates were used to prove the truth of the matter they
asserted. Under state law, “the sole purpose of the affidavits was
to provide prima facie evidence of the composition, quality, and
the net weight of the analyzed substance.” Ibid. (internal
quotation marks omitted and emphasis deleted). On these facts, the
Court said, it was clear that the certif- icates were “testimonial
statements” that could not be introduced unless their authors were
subjected to the “ ‘cru- cible of cross-examination.’ ”
Id., at 311, 317 (quoting Crawford, supra, at 61).

															In Bullcoming, we held that another scientific
report could not be used as substantive evidence against the de-
fendant unless the analyst who prepared and certified the report
was subject to confrontation. The defendant in that case had been
convicted of driving while intoxicated. At trial, the court
admitted into evidence a forensic report certifying that a sample
of the defendant’s blood had an alcohol concentration of 0.21 grams
per hundred milli- liters, well above the legal limit. Instead of
calling the analyst who signed and certified the forensic report,
the prosecution called another analyst who had not performed or
observed the actual analysis, but was only familiar with the
general testing procedures of the laboratory. The Court declined to
accept this surrogate testimony, despite the fact that the
testifying analyst was a “knowledgeable representative of the
laboratory” who could “explain the lab’s processes and the details
of the report.” 564 U. S., at ___ (Kennedy, J., dissenting)
(slip op., at 1). The Court stated simply: “The accused’s right is
to be confronted with the analyst who made the certification.” Id.,
at ___ (slip op., at 2).

															Just as in Melendez-Diaz, the forensic report
that was “introduce[d]” in Bullcoming “contain[ed] a testimonial
certification, made in order to prove a fact at a criminal trial.”
564 U. S., at ___–___ (slip op., at 7–8). The report was
signed by the nontestifying analyst who had authored it, stating,
“I certify that I followed the procedures set out on the reverse of
this report, and the statements in this block are correct. The
concentration of alcohol in this sample is based on the grams of
alcohol in one hundred milliliters of blood.” App. in Bullcoming,
O. T. 2010, No. 09–10876, p. 62. Critically, the
report was introduced at trial for the substantive purpose of
proving the truth of the matter asserted by its out-of-court
author—namely, that the defendant had a blood-alcohol level of
0.21. This was the central fact in question at the defendant’s
trial, and it was dispositive of his guilt.

															In concurrence, Justice Sotomayor highlighted
the im- portance of the fact that the forensic report had been
admitted into evidence for the purpose of proving the truth of the
matter it asserted. She emphasized that “this [was] not a case in
which an expert witness was asked for his independent opinion about
underlying testimonial reports that were not themselves admitted
into evidence.” 564 U. S., at ___ (slip op., at 6) (opinion
concurring in part) (citing Fed. Rule Evid. 703). “We would face a
different question,” she observed, “if asked to determine the
constitutionality of allowing an expert witness to discuss others’
testimonial statements if the testimonial statements were not
themselves admitted as evidence.” Id., at ___ (slip op., at 6).

															We now confront that question.

															B

															It has long been accepted that an expert
witness may voice an opinion based on facts concerning the events
at issue in a particular case even if the expert lacks first-hand
knowledge of those facts.

															At common law, courts developed two ways to deal
with this situation. An expert could rely on facts that had already
been established in the record. But because it was not always
possible to proceed in this manner, and because record evidence was
often disputed, courts developed the alternative practice of
allowing an expert to testify in the form of a “hypothetical
question.” Under this approach, the expert would be asked to assume
the truth of certain factual predicates, and was then asked to
offer an opinion based on those assumptions. See 1 K. Broun,
McCormick on Evidence §14, p. 87 (6th ed. 2006); 1 J. Wigmore,
Evidence §677, p. 1084 (2d ed. 1923) (“If the witness is skilled
enough, his opinion may be adequately obtained upon hypothetical
data alone; and it is immate- rial whether he has ever seen the
person, place or thing in question” (citation omitted)). The truth
of the premises could then be established through independent
evidence, and the factfinder would regard the expert’s testimony to
be only as credible as the premises on which it was based.

															An early example of this approach comes from the
English case of Beckwith v. Sydebotham, 1 Camp. 116, 170 Eng. Rep.
897 (K. B. 1807), where a party sought to prove the
seaworthiness of a ship, the Earl of Wycombe, by calling as
witnesses “several eminent surveyors of ships who had never seen
the ‘Earl of Wycombe.’ ” Ibid. The opposing party objected to
the testimony because it relied on facts that were not known to be
true, but the judge disagreed. Because the experts were “peculiarly
ac- quainted” with “a matter of skill or science,” the judge said,
the “jury might be assisted” by their hypothetical opinion based on
certain assumed facts. Id., at 117, 170 Eng. Rep., at 897. The
judge acknowledged the danger of the jury’s being unduly prejudiced
by wrongly assuming the truth of the hypothetical facts, but the
judge noted that the experts could be asked on cross-examination
what their opinion of the ship’s seaworthiness would be if
different hypothetical facts were assumed. If the party that had
called the experts could not independently prove the truth of the
premises they posited, then the experts’ “opinion might not go for
much; but still it was admissible evidence.” Ibid.

															There is a long tradition of the use of
hypothetical questions in American courts. In 1887, for example,
this Court indicated its approval of the following jury
instruction:

															“As to the questions, you must understand
that they are not evidence; they are mere statements to these
witnesses . . . and, upon the hypothesis or assumption of
these questions the witnesses are asked to give their [opinion].
You must readily see that the value of the answers to these
questions depends largely, if not wholly, upon the fact whether the
statements made in these questions are sustained by the proof. If
the statements in these questions are not supported by the proof,
then the answers to the questions are entitled to no weight,
because based upon false assumptions or statements of facts.”
Forsyth v. Doolittle, 120 U.S.
73 (internal quotation marks omitted).

															Modern rules of evidence continue to permit
experts to express opinions based on facts about which they lack
personal knowledge, but these rules dispense with the need for
hypothetical questions. Under both the Illinois and the Federal
Rules of Evidence, an expert may base an opinion on facts that are
“made known to the expert at or before the hearing,” but such
reliance does not constitute admissible evidence of this underlying
information. Ill. Rule Evid. 703; Fed. Rule Evid. 703. Accordingly,
in jury trials, both Illinois and federal law generally bar an
expert from disclosing such inadmissible evidence. [ 2 ] In bench trials, however, both the
Illinois and the Federal Rules place no restriction on the
revelation of such information to the factfinder. When the judge
sits as the trier of fact, it is presumed that the judge will
understand the limited reason for the disclosure of the underlying
inadmissible information and will not rely on that information for
any improper purpose. As we have noted, “[i]n bench trials, judges
routinely hear inadmissible evidence that they are presumed to
ignore when making decisions.” Harris v. Rivera, 454 U.S.
339 , 346 (1981) (per curiam). There is a “well-established
presumption” that “the judge [has] adhered to basic rules of
procedure,” when the judge is acting as a factfinder. Id., at
346–347 (emphasis added). See also Gentile v. State Bar of Nev., 501 U.S.
1030 , 1078 (1991) (Rehnquist, C. J., dissenting).

															This feature of Illinois and federal law is
important because Crawford, while departing from prior
Confrontation Clause precedent in other respects, took pains to
reaffirm the proposition that the Confrontation Clause “does not
bar the use of testimonial statements for purposes other than
establishing the truth of the matter asserted.” 541 U. S., at
59–60, n. 9 (citing Tennessee v. Street, 471
U.S. 409 ). In Street, the defendant claimed that the police
had coerced him into adopting the confession of his alleged
accomplice. The prosecution sought to rebut this claim by showing
that the defendant’s confession differed significantly from the
accomplice’s. Although the accomplice’s confession was clearly a
testimonial statement, the Court held that the jurors could hear it
as long as they were instructed to consider that confession not for
its truth, but only for the “distinctive and limited purpose” of
comparing it to the defendant’s confession, to see whether the two
were identical. Id., at 417.

															III

															A

															In order to assess petitioner’s Confrontation
Clause argument, it is helpful to inventory exactly what Lambatos
said on the stand about Cellmark. She testified to the truth of the
following matters: Cellmark was an accredited lab, App. 49; the ISP
occasionally sent forensic samples to Cellmark for DNA testing,
ibid.; according to shipping manifests admitted into evidence, the
ISP lab sent vaginal swabs taken from the victim to Cellmark and
later received those swabs back from Cellmark, id., at 52–55; and,
finally, the Cellmark DNA profile matched a profile produced by the
ISP lab from a sample of petitioner’s blood, id., at 55–56.
Lambatos had personal knowledge of all of these matters, and
therefore none of this testimony in- fringed petitioner’s
confrontation right.

															Lambatos did not testify to the truth of any
other matter concerning Cellmark. She made no other reference to
the Cellmark report, which was not admitted into evidence and was
not seen by the trier of fact. Nor did she testify to anything that
was done at the Cellmark lab, and she did not vouch for the quality
of Cellmark’s work.

															B

															The principal argument advanced to show a
Confrontation Clause violation concerns the phrase that Lambatos
used when she referred to the DNA profile that the ISP lab received
from Cellmark. This argument is developed most fully in the
dissenting opinion, and therefore we refer to the dissent’s
discussion of this issue.

															In the view of the dissent, the following is the
critical portion of Lambatos’ testimony, with the particular words
that the dissent finds objectionable italicized:

															“Q Was there a computer match generated of the
male DNA profile found in semen from the vaginal swabs of [L.J.] to
a male DNA profile that had been identified as having originated
from Sandy Williams?

															“A Yes, there was.” Post, at 7 (opinion of
Kagan, J.) (quoting App. 56; emphasis added).

															According to the dissent, the italicized phrase
violated petitioner’s confrontation right because Lambatos lacked
personal knowledge that the profile produced by Cellmark was based
on the vaginal swabs taken from the victim, L. J. As the
dissent acknowledges, there would have been “nothing wrong with
Lambatos’s testifying that two DNA profiles—the one shown in the
Cellmark report and the one derived from Williams’s blood—matched
each other; that was a straightforward application of Lambatos’s
expertise.” Post, at 12. Thus, if Lambatos’ testimony had been
slightly modified as follows, the dissent would see no problem:

															“Q Was there a computer match generated of the
male DNA profile produced by Cellmark found in semen from the
vaginal swabs of [L.J.] to a male DNA profile that had been
identified as having originated from Sandy Williams?

															“A Yes, there was.” [ 3 ]

															The defect in this argument is that under
Illinois law (like federal law) it is clear that the putatively
offending phrase in Lambatos’ testimony was not admissible for the
purpose of proving the truth of the matter asserted—i.e., that the
matching DNA profile was “found in semen from the vaginal swabs.”
Rather, that fact was a mere premise of the prosecutor’s question,
and Lambatos simply assumed that premise to be true when she gave
her answer indicating that there was a match between the two DNA
profiles. There is no reason to think that the trier of fact took
Lambatos’ answer as substantive evidence to establish where the DNA
profiles came from.

															The dissent’s argument would have force if
petitioner had elected to have a jury trial. In that event, there
would have been a danger of the jury’s taking Lambatos’ testimony
as proof that the Cellmark profile was derived from the sample
obtained from the victim’s vaginal swabs. Absent an evaluation of
the risk of juror confusion and careful jury instructions, the
testimony could not have gone to the jury.

															This case, however, involves a bench trial and
we must assume that the trial judge understood that the portion of
Lambatos’ testimony to which the dissent objects was not admissible
to prove the truth of the matter asserted. [ 4 ] The dissent, on the other hand, reaches the
truly remarkable conclusion that the wording of Lambatos’ testimony
confused the trial judge. Were it not for that wording, the
argument goes, the judge might have found that the prosecution
failed to introduce sufficient admissible evidence to show that the
Cellmark profile was derived from the sample taken from the victim,
and the judge might have disregarded the DNA evidence. This
argument reflects a profound lack of respect for the acumen of the
trial judge. [ 5 ]

															To begin, the dissent’s argument finds no
support in the trial record. After defense counsel objected to
Lambatos’ testimony, the prosecutor made clear that she was asking
Lambatos only about “her own testing based on [DNA] information”
that she had received from Cellmark. App. 56. Recognizing that
Lambatos’ testimony would carry weight only if the underlying
premises could be established, the judge noted that “the issue is
. . . what weight do you give the test [performed by
Lambatos], not do you exclude it.” Id., at 94. This echoes the old
statement in Beckwith that an expert’s opinion based on disputed
premises “might not go for much; but still it [is] admissible
evidence.” 1 Camp., at 117, 170 Eng. Rep., at 897. Both the
Illinois Appellate Court and the Illinois Supreme Court viewed the
record in this way, and we see no ground for disagreement. [ 6 ]

															Second, it is extraordinarily unlikely that any
trial judge would be confused in the way that the dissent posits.
That Lambatos was not competent to testify to the chain of custody
of the sample taken from the victim was a point that any trial
judge or attorney would immediately understand. Lambatos, after
all, had absolutely nothing to do with the collection of the sample
from the victim, its subsequent handling or preservation by the
police in Illinois, or its shipment to and receipt by Cellmark. No
trial judge would take Lambatos’ testimony as furnishing “the
missing link” in the State’s evidence regarding the identity of the
sample that Cellmark tested. See post, at 6 (opinion of Kagan,
J.).

															Third, the admissible evidence left little room
for argument that the sample tested by Cellmark came from any
source other than the victim’s vaginal swabs. [ 7 ] This is so because there is simply no
plausible explanation for how Cellmark could have produced a DNA
profile that matched Williams’ if Cellmark had tested any sample
other than the one taken from the victim. If any other items that
might have contained Williams’ DNA had been sent to Cellmark or
were otherwise in Cellmark’s possession, there would have been a
chance of a mix-up or of cross-contamination. See District
Attorney’s Office for Third Judicial Dist. v. Osborne, 557 U.S. 52,
80 (2009) (Alito, J., concurring). But there is absolutely nothing
to suggest that Cellmark had any such items. Thus, the fact that
the Cellmark profile matched Williams—the very man whom the victim
identified in a lineup and at trial as her at- tacker—was itself
striking confirmation that the sample that Cellmark tested was the
sample taken from the victim’s vaginal swabs. For these reasons, it
is fanciful to suggest that the trial judge took Lambatos’
testimony as providing critical chain-of-custody evidence.

															C

															Other than the phrase that Lambatos used in
referring to the Cellmark profile, no specific passage in the trial
record has been identified as violating the Confrontation Clause,
but it is nevertheless suggested that the State somehow introduced
“the substance of Cellmark’s report into evidence.” Post, at 8
(Kagan, J., dissenting). The main impetus for this argument appears
to be the (erroneous) view that unless the substance of the report
was sneaked in, there would be insufficient evidence in the record
on two critical points: first, that the Cellmark profile was based
on the semen in the victim’s vaginal swabs and, second, that
Cellmark’s procedures were reli- able. This argument is both
legally irrelevant for present purposes and factually
incorrect.

															As to legal relevance, the question before us is
whether petitioner’s Sixth Amendment confrontation right was
violated, not whether the State offered sufficient foundational
evidence to support the admission of Lambatos’ opinion about the
DNA match. In order to prove these underlying facts, the
prosecution relied on circumstantial evidence, and the Illinois
courts found that this evidence was sufficient to satisfy state-law
requirements regarding proof of foundational facts. See 385 Ill.
App. 3d, at 366–368, 895 N. E. 2d, at 967–968; 238 Ill. 2d, at 138,
939 N. E. 2d, at 275. We cannot review that interpretation and
application of Illinois law. Thus, even if the record did not
contain any evidence that could rationally support a finding that
Cellmark produced a scientifically reliable DNA profile based on L.
J.’s vaginal swab, that would not establish a Confrontation Clause
violation. If there were no proof that Cellmark produced an
accurate profile based on that sample, Lambatos’ testimony
regarding the match would be irrelevant, but the Confrontation
Clause, as interpreted in Crawford, does not bar the admission of
irrelevant evidence, only testimonial statements by declarants who
are not subject to cross-examination. [ 8 ]

															It is not correct, however, that the trial
record lacks admissible evidence with respect to the source of the
sam- ple that Cellmark tested or the reliability of the Cell- mark
profile. As to the source of the sample, the State offered
conventional chain-of-custody evidence, namely, the testimony of
the physician who obtained the vaginal swabs, the testimony of the
police employees who handled and kept custody of that evidence
until it was sent to Cellmark, and the shipping manifests, which
provided evidence that the swabs were sent to Cellmark and then
returned to the ISP lab. In addition, as already discussed, the
match between the Cellmark profile and petitioner’s profile was
itself telling confirmation that the Cellmark profile was deduced
from the semen on the vaginal swabs.

															This match also provided strong circumstantial
evidence regarding the reliability of Cellmark’s work. Assuming
(for the reasons discussed above) that the Cellmark profile was
based on the semen on the vaginal swabs, how could shoddy or
dishonest work in the Cellmark lab [ 9 ] have resulted in the production of a DNA profile that
just so happened to match petitioner’s? If the semen found on the
vaginal swabs was not petitioner’s and thus had an en- tirely
different DNA profile, how could sloppy work in the Cellmark lab
have transformed that entirely different profile into one that
matched petitioner’s? And without access to any other sample of
petitioner’s DNA (and recall that petitioner was not even under
suspicion at this time), how could a dishonest lab technician have
substituted pe- titioner’s DNA profile? Under the circumstances of
this case, it was surely permissible for the trier of fact to infer
that the odds of any of this were exceedingly low.

															This analysis reveals that much of the dissent’s
argument rests on a very clear error. The dissent argues that
Lambatos’ testimony could be “true” only if the predicate facts
asserted in the Cellmark report were true, and therefore Lambatos’
reference to the report must have been used for the purpose of
proving the truth of those facts. See post, at 10–11. But the truth
of Lambatos’ testimony, properly understood, was not dependent on
the truth of any predicate facts. Lambatos testified that two DNA
profiles matched. The correctness of this expert opinion, which the
defense was able to test on cross-examination, was not in any way
dependent on the origin of the samples from which the profiles were
derived. Of course, Lambatos’ opinion would have lacked probative
value if the prosecution had not introduced other evidence to
establish the provenance of the profiles, but that has nothing to
do with the truth of her testimony.

															The dissent is similarly mistaken in its
contention that the Cellmark report “was offered for its truth
because that is all such ‘basis evidence’ can be offered for.”
Post, at 13; see also post, at 3 (Thomas, J., concurring in
judgment) (“[S]tatements introduced to explain the basis of an
expert’s opinion are not introduced for a plausible nonhearsay
purpose”). This view is directly contrary to the current version of
Rule 703 of the Federal Rules of Evidence, which this Court
approved and sent to Congress in 2000. Under that Rule, “basis
evidence” that is not admissible for its truth may be disclosed
even in a jury trial under appropriate circumstances. The purpose
for allowing this disclosure is that it may “assis[t] the jury to
evaluate the expert’s opinion.” Advisory Committee’s 2000 Notes on
Fed. Rule Evid. 703, 28 U. S. C. App., p. 361. The Rule
703 approach, which was controversial when adopted, [ 10 ] is based on the idea that the
disclosure of basis evidence can help the factfinder understand the
expert’s thought process and determine what weight to give to the
expert’s opinion. For example, if the factfinder were to suspect
that the expert relied on factual premises with no support in the
record, or that the expert drew an unwarranted inference from the
premises on which the expert relied, then the probativeness or
credibility of the expert’s opinion would be seriously undermined.
The purpose of disclosing the facts on which the expert relied is
to allay these fears—to show that the expert’s reasoning was not
illogical, and that the weight of the expert’s opinion does not
depend on factual premises unsupported by other evidence in the
record—not to prove the truth of the underlying facts.

															Perhaps because it cannot seriously dispute the
legit- imate nonhearsay purpose of illuminating the expert’s
thought process, the dissent resorts to the last-ditch argument
that, after all, it really does not matter whether Lambatos’
statement regarding the source of the Cellmark report was admitted
for its truth. The dissent concedes that “the trial judge might
have ignored Lambatos’s statement about the Cellmark report,” but
nonetheless maintains that “the admission of that statement
violated the Confrontation Clause even if the judge ultimately put
it aside.” Post, at 15, n. 2. But in a bench trial, it is not
necessary for the judge to stop and make a formal statement on the
record regarding the limited reason for which the testimony is
admitted. If the judge does not consider the testimony for its
truth, the effect is precisely the same. Thus, if the trial judge
in this case did not rely on the statement in question for its
truth, there is simply no way around the proviso in Crawford that
the Confrontation Clause applies only to out-of-court statements
that are “use[d]” to “establis[h] the truth of the matter
asserted.” 541 U. S., at 59–60, n. 9 (citing Street, 471
U.S. 409 ).

															For all these reasons, we conclude that
petitioner’s Sixth Amendment confrontation right was not
violated.

															D

															This conclusion is entirely consistent with
Bullcoming and Melendez-Diaz. In those cases, the forensic reports
were introduced into evidence, and there is no question that this
was done for the purpose of proving the truth of what they
asserted: in Bullcoming that the defendant’s blood alcohol level
exceeded the legal limit and in Melendez- Diaz that the substance
in question contained cocaine. Nothing comparable happened here. In
this case, the Cellmark report was not introduced into evidence. An
expert witness referred to the report not to prove the truth of the
matter asserted in the report, i.e., that the report contained an
accurate profile of the perpetrator’s DNA, but only to establish
that the report contained a DNA profile that matched the DNA
profile deduced from petitioner’s blood. Thus, just as in Street,
the report was not to be considered for its truth but only for the
“distinctive and limited purpose” of seeing whether it matched
something else. 471 U. S., at 417. The relevance of the match
was then established by independent circumstantial evidence showing
that the Cellmark report was based on a forensic sample taken from
the scene of the crime.

															Our conclusion will not open the door for the
kind of abuses suggested by some of petitioner’s amici and the
dissent. See post, at 10–11; Brief for Richard D. Friedman as
Amicus Curiae 20–21. In the hypothetical situations posited, an
expert expresses an opinion based on factual premises not supported
by any admissible evidence, and may also reveal the out-of-court
statements on which the expert relied. [ 11 ] There are at least four safeguards to prevent
such abuses. First, trial courts can screen out experts who would
act as mere conduits for hearsay by strictly enforcing the
requirement that experts display some genuine “scientific,
technical, or other specialized knowledge [that] will help the
trier of fact to understand the evidence or to determine a fact in
issue.” Fed. Rule Evid. 702(a). Second, experts are generally
precluded from disclosing inadmissible evidence to a jury. See Fed.
Rule Evid. 703; People v. Pasch, 152 Ill. 2d 133 , 175–176, 604 N.E.2d 294 , 310–311 (1992). Third, if such evidence is
disclosed, the trial judges may and, under most circumstances,
must, instruct the jury that out-of-court statements cannot be
accepted for their truth, and that an expert’s opinion is only as
good as the independent evidence that establishes its underlying
premises. See Fed. Rules Evid. 105, 703; People v. Scott, 148 Ill. 2d 479 , 527–528, 594 N.E.2d 217 , 236–237 (1992). And fourth, if the prosecution
cannot muster any independent admissible evidence to prove the
foundational facts that are essential to the relevance of the
expert’s testimony, then the expert’s testimony cannot be given any
weight by the trier of fact. [ 12 ]

															IV

															A

															Even if the Cellmark report had been
introduced for its truth, we would nevertheless conclude that there
was no Confrontation Clause violation. The Confrontation Clause
refers to testimony by “witnesses against” an accused. Both the
noted evidence scholar James Henry Wigmore and Justice Harlan
interpreted the Clause in a strictly literal sense as referring
solely to persons who testify in court, but we have not adopted
this narrow view. It has been said that “[t]he difficulty with the
Wigmore-Harlan view in its purest form is its tension with much of
the apparent history surrounding the evolution of the right of
confrontation at common law.” White v. Illinois, 502 U.S.
346 , 360 (1992) (Thomas, J., concurring). “[T]he principal evil
at which the Confrontation Clause was directed,” the Court
concluded in Crawford, “was the civil-law mode of criminal
procedure, and particularly its use of ex parte examinations as
evidence against the accused.” 541 U. S., at 50. “[I]n
England, pretrial examinations of suspects and witnesses by
government officials ‘were sometimes read in court in lieu of live
testimony.’ ” Bryant, 562 U. S., at ___ (slip op., at 6)
(quoting Crawford, supra, at 43). The Court has thus interpreted
the Confrontation Clause as prohibiting modern-day practices that
are tantamount to the abuses that gave rise to the recognition of
the confrontation right. But any further expansion would strain the
constitutional text.

															The abuses that the Court has identified as
prompting the adoption of the Confrontation Clause shared the
following two characteristics: (a) they involved out-of-court
statements having the primary purpose of accusing a targeted
individual of engaging in criminal conduct and (b) they involved
formalized statements such as affidavits, depositions, prior
testimony, or confessions. In all but one of the post-Crawford
cases [ 13 ] in which a
Confrontation Clause violation has been found, both of these
characteristics were present. See Bullcoming, 564 U. S., at
308 (slip op., at 3–4) (certified lab report having purpose of
showing that defendant’s blood-alcohol level exceeded legal limit);
Melendez-Diaz, 557 U. S., at 308 (certified lab report having
purpose of showing that substance connected to defendant contained
cocaine); Crawford, supra, at 38 (custodial statement made after
Miranda warnings that shifted blame from declarant to accused). [ 14 ] The one exception
occurred in Hammon v. Indiana, 547
U.S. 813 –832 (2006), which was decided together with Davis v.
Washington, but in Hammon and every other post-Crawford case in
which the Court has found a violation of the confrontation right,
the statement at issue had the primary purpose of accusing a
targeted individual.

															B

															In Hammon, the one case in which an informal
statement was held to violate the Confrontation Clause, we
considered statements elicited in the course of police in-
terrogation. We held that a statement does not fall within the
ambit of the Clause when it is made “under circumstances
objectively indicating that the primary purpose of the
interrogation is to enable police assistance to meet an ongoing
emergency.” 547 U. S., at 822. In Bryant, another
police-interrogation case, we explained that a person who makes a
statement to resolve an ongoing emergency is not acting like a
trial witness because the declarant’s purpose is not to provide a
solemn declaration for use at trial, but to bring an end to an
ongoing threat. See 562 U. S., at ___, ___ (slip op., at 11,
14). We noted that “the prospect of fabrication . . . is
presumably significantly diminished” when a statement is made under
such circumstances, id., at ___ (slip op., at 14) and that
reliability is a salient characteristic of a statement that falls
outside the reach of the Confrontation Clause, id., at ___–___
(slip op., at 14–15). We emphasized that if a statement is not made
for “the primary purpose of creating an out-of-court substitute for
trial testimony,” its admissibility “is the concern of state and
federal rules of evidence, not the Confrontation Clause.” Id., at
___–___ (slip op., at 11–12).

															In Melendez-Diaz and Bullcoming, the Court held
that the particular forensic reports at issue qualified as
testimonial statements, but the Court did not hold that all
forensic reports fall into the same category. Introduction of the
reports in those cases ran afoul of the Confrontation Clause
because they were the equivalent of affidavits made for the purpose
of proving the guilt of a particular criminal defendant at trial.
There was nothing resembling an ongoing emergency, as the suspects
in both cases had already been captured, and the tests in question
were relatively simple and can generally be performed by a single
analyst. In addition, the technicians who prepared the reports must
have realized that their contents (which reported an elevated
blood-alcohol level and the presence of an illegal drug) would be
incriminating.

															C

															The Cellmark report is very different. It
plainly was not prepared for the primary purpose of accusing a
targeted individual. In identifying the primary purpose of an
out-of-court statement, we apply an objective test. Bryant, 562
U. S., at ___ (slip op., at 13). We look for the primary
purpose that a reasonable person would have ascribed to the
statement, taking into account all of the surrounding
circumstances. Ibid.

															Here, the primary purpose of the Cellmark
report, viewed objectively, was not to accuse petitioner or to
create evidence for use at trial. When the ISP lab sent the sample
to Cellmark, its primary purpose was to catch a dangerous rapist
who was still at large, not to obtain evidence for use against
petitioner, who was neither in custody nor under suspicion at that
time. Similarly, no one at Cellmark could have possibly known that
the profile that it produced would turn out to inculpate
petitioner—or for that matter, anyone else whose DNA profile was in
a law enforcement database. Under these circumstances, there was no
“prospect of fabrication” and no incentive to produce anything
other than a scientifi- cally sound and reliable profile. Id., at
___ (slip op., at 14).

															The situation in which the Cellmark technicians
found themselves was by no means unique. When lab technicians are
asked to work on the production of a DNA profile, they often have
no idea what the consequences of their work will be. In some cases,
a DNA profile may provide powerful incriminating evidence against a
person who is identified either before or after the profile is
completed. But in others, the primary effect of the profile is to
exonerate a suspect who has been charged or is under investigation.
The technicians who prepare a DNA profile generally have no way of
knowing whether it will turn out to be incriminating or
exonerating—or both.

															It is also significant that in many labs,
numerous technicians work on each DNA profile. See Brief for New
York County District Attorney’s Office et al. as Amici Curiae
6 (New York lab uses at least 12 technicians for each case); People
v. Johnson, 389 Ill. App. 3d 618, 627, 906 N.E.2d 70, 79 (2009)
(“[A]pproximately 10 Cellmark analysts were involved in the
laboratory work in this case”). When the work of a lab is divided
up in such a way, it is likely that the sole purpose of each
technician is simply to perform his or her task in accordance with
accepted procedures.

															Finally, the knowledge that defects in a DNA
profile may often be detected from the profile itself provides a
further safeguard. In this case, for example, Lambatos testified
that she would have been able to tell from the profile if the
sample used by Cellmark had been degraded prior to testing. As
noted above, moreover, there is no real chance that “sample
contamination, sample switching, mislabeling, [or] fraud” could
have led Cellmark to produce a DNA profile that falsely matched
petitioner. Post, at 21 (Kagan, J., dissenting). At the time of the
testing, petitioner had not yet been identified as a suspect, and
there is no suggestion that anyone at Cellmark had a sample of his
DNA to swap in by malice or mistake. And given the complexity of
the DNA molecule, it is inconceivable that shoddy lab work would
somehow produce a DNA profile that just so happened to have the
precise genetic makeup of petitioner, who just so happened to be
picked out of a lineup by the victim. The prospect is beyond
fanciful.

															In short, the use at trial of a DNA report
prepared by a modern, accredited laboratory “bears little if any
resemblance to the historical practices that the Confrontation
Clause aimed to eliminate.” Bryant, supra, at ___ (slip op., at 2)
(Thomas, J., concurring).

															*  *  *

															For the two independent reasons explained
above, we conclude that there was no Confrontation Clause violation
in this case. Accordingly, the judgment of the Supreme Court of
Illinois is

															Affirmed. Notes 1 Consistent with the
Federal Rules, Illinois Rule of Evidence 703 provides as follows:
“The facts or data in the particular case upon which an expert
bases an opinion or inference may be those perceived by or made
known to the expert at or before the hearing. If of a type
reasonably relied upon by experts in the particular field in
forming opinions or inferences upon the subject, the facts or data
need not be admissible inevidence.” 2 But disclosure of these
facts or data to the jury is permitted if the value of disclosure
“substantially outweighs [any] prejudicial effect,” Fed. Rule Evid.
703, or “the probative value . . . outweighs the risk of unfair
prejudice.” People v. Pasch, 152 Ill. 2d 133 , 223, 604 N.E.2d 294 , 333 (1992). When this disclosure occurs, “the
underlying facts” are revealed to the jury “for the limited purpose
of explaining the basis for [the expert’s] opinion” and not “for
the truth of the matter asserted.” Id., at 176, 604 N. E. 2d,
at 311. 3 The small difference
between what Lambatos actually said on the stand and the slightly
revised version that the dissent would find un-objectionable shows
that, despite the dissent’s rhetoric, its narrow argument would
have little practical effect in future cases. Prosecutors would be
allowed to do exactly what the prosecution did in this case so long
as their testifying experts’ testimony was slightly modified along
the lines shown above. Following that course presumably would not
constitute a “prosecutorial dodge,” “subterfuge,” “indirection,”
the “neat trick” of “sneak[ing]” in evidence, or the countenancing
of constitutional violations with “a wink and a nod.” See post, at
3, 16, 17, 12 (opinion of Kagan, J.). 4 We do not suggest that
the Confrontation Clause applies differently depending on the
identity of the factfinder. Cf. post, at 14–15 (opinion of Kagan,
J.). Instead, our point is that the identity of the factfinder
makes a big difference in evaluating the likelihood that the
factfinder mistakenly based its decision on inadmissible
evidence. 5 See post, at 14 (opinion
of Kagan, J.) (“I do not doubt that a judge typically will do
better than a jury in excluding such inadmissible evidence from his
decisionmaking process. Perhaps the judge did so here” (emphasis
added)). 6 The dissent finds
evidence of the trial judge’s confusion in his statement that
petitioner is “ ‘the guy whose DNA, according to the evidence
from the experts, is in the semen recovered from the victim’s
vagina.’ ” Post, at 14 (emphasis added). The dissent
interprets the phrase “according to the evidence from the experts”
as a reference to what one expert, Lambatos, said about the origin
of the sample that Cellmark tested. In context, however, the
judge’s statement is best understood as attributing to Lambatos
nothing more than the conclusion that there was a match between the
two DNA profiles that were compared. The foundational facts, that
one of the profiles came from the defendant and that the other came
from “ ‘the semen recovered from the victim’s vagina,’ ”
were established not by expert testimony but by ordinary
chain-of-custody evidence. 7 Our point is not that
admissible evidence regarding the identity of the sample that
Cellmark tested excuses the admission of testimonial hearsay on
this matter. Compare post, at 5–6 (Thomas, J., concurring in
judgment), with post, at 14 (Kagan, J., dissenting). Rather, our
point is that, because there was substantial (albeit
circumstantial) evidence on this matter, there is no reason to
infer that the trier of fact must have taken Lambatos’ statement as
providing “the missing link.” 8 Applying the Due Process
Clause, we have held that a federal court may determine whether a
rational trier of fact could have found the existence of all the
elements needed for conviction for a state offense. Jackson v.
Virginia, 443 U.S.
307 , 314 (1979) , but petitioner has not raised a due process
claim. And in any event, L. J.’s identification of petitioner as
her assailant would be sufficient to defeat any such
claim. 9 See post, at 18 (Kagan,
J., dissenting). 10 See
Advisory Committee’s 2000 Notes on Rule 703, at 361. 11 Both
Justice Thomas and Justice Kagan quote statements in D. Kaye, D.
Bernstein, & J. Mnookin, The New Wigmore: Expert Evidence
§4.10.1, pp. 196–197 (2d ed. 2011) (hereinafter New Wigmore), that
are critical of the theory that an expert, without violating the
Confrontation Clause, may express an opinion that is based on
testimonial hearsay and may, in some circumstances, disclose that
testimonial hearsay to the trier of fact. The principal basis for
this criticism seems to be the fear that juries, even if given
limiting instructions, will view the disclosed hearsay as evidence
of the truth of the matter asserted. See id., at 196, n. 36
(referring reader to the more detailed discussion in Mnookin,
Expert Evidence and the Confrontation Clause After Crawford v.
Washington, 15 J. L. & Pol’y 791 (2007)); New Wigmore
197,and n. 39 (citing jury cases); Mnookin, supra, at 802–804,
811–813. This argument plainly has no application in a case like
this one, in which a judge sits as the trier of fact. In the 2012
Supplement of The New Wigmore, the authors discuss the present case
and criticize the reasoning of the Illinois courts as follows: “The
problem with [the not-for-the-truth-of-the-matter argument accepted
by the Illinois courts] is that Lambatos had to rely on the truth
of the statements in the Cellmark report to reach her own
conclusion. The claim that evidence that the jury must credit in
order to credit the conclusion of the expert is introduced for
something other than its truth is sheer fiction.” New Wigmore
§4.11.6, at 24 (2012 Supp.) (emphasis added). This discussion is
flawed. It overlooks the fact that there was no jury in this case,
and as we have explained, the trier of fact did not have to rely on
any testimonial hearsay in order to find that Lambatos’ testimony
about the DNA match was supported by adequate foundational evidence
and was thus probative. 12 Our
discussion of the first ground for our decision cannot conclude
without commenting on the Kocak case, which dramatically appears at
the beginning of the dissent. In that case, a Cellmark lab analyst
realized while testifying at a pretrial hearing that there was an
error in the lab’s report and that the DNA profile attributed to
the accused was actually that of the victim. The lesson of this
cautionary tale is nothing more than the truism that it is possible
for an apparently incriminating DNA profile to be mistakenly
attributed to an accused. But requiring that the lab analyst or
analysts who produced the DNA profile be called as prosecution
witnesses is neither sufficient nor necessary to prevent such
errors. Since samples may be mixed up or contaminated at many
points along the way from a crime scene to the lab, calling one or
more lab analysts will not necessarily catch all such mistakes. For
example, a mistake might be made by a clerical employee responsible
for receiving shipments of samples and then providing them to the
lab’s technicians. What is needed is for the trier of fact to make
sure that the evidence, whether direct or circumstantial, rules out
the possibility of such mistakes at every step along the way. And
in the usual course of authentication, defense counsel will have
access to sufficient information to inquire into, question, or
challenge the procedures used by a laboratory if this seems to be a
prudent and productive strategy. 13 Experience might yet show that the
holdings in those cases should be reconsidered for the reasons,
among others, expressed in the dissents the decisions produced.
Those decisions are not challenged in this case and are to be
deemed binding precedents, but they can and should be distinguished
on the facts here. 14 With
respect to Crawford, see Davis, 547 U. S., at 840 (Thomas, J.,
concurring in judgment in part and dissenting in
part). SUPREME COURT OF THE UNITED STATES

															_________________

															No. 10–8505

															_________________

															SANDY WILLIAMS, PETITIONER v. ILLINOIS

															on writ of certiorari to the supreme court of
illinois

															[June 18, 2012]

															Justice Breyer, concurring.

															This case raises a question that I believe
neither the plurality nor the dissent answers adequately: How does
the Confrontation Clause apply to the panoply of crime laboratory
reports and underlying technical statements written by (or
otherwise made by) laboratory technicians? In this context, what,
if any, are the outer limits of the “testimonial statements” rule
set forth in Crawford v. Washington, 541 U.S.
36 (2004) ? Because I believe the question difficult,
important, and not squarely addressed either today or in our
earlier opinions, and because I believe additional briefing would
help us find a proper, generally applicable answer, I would set
this case for reargument. In the absence of doing so, I adhere to
the dissenting views set forth in Melendez-Diaz v. Massachusetts, 557 U.S.
305 (2009) , and Bullcoming v. New Mexico, 564 U. S. ___
(2011). I also join the plurality’s opinion.

															I

															A

															This case is another in our series involving
the inter-section of the Confrontation Clause and expert testimony.
Before trial, the prosecution’s expert, Sandra Lambatos, received a
copy of a report prepared by Cellmark Diagnostics Laboratory. That
report reflected the fact that Cellmark technicians had received
material from a vaginal swab taken from the crime victim, had
identified semen in that material, and had derived a profile of the
male DNA that the semen contained. Lambatos then entered that
profile into an Illinois State Police Crime Laboratory computerized
database, which contained, among many other DNA profiles, a profile
derived by the crime laboratory from Williams’ blood (taken at an
earlier time). The computer she was using showed that the two
profiles matched. Lambatos then confirmed the match.

															Later, Lambatos testified at trial, where the
prosecutor asked her three relevant questions. First, the
prosecutor asked whether there was “a computer match generated of
the male DNA profile [derived by Cellmark] found in [the] semen
from the vaginal swabs . . . to [the] male DNA profile
[found in the database] that had been identified as having
originated from Sandy Williams”? App. 56. Since the computer had
shown such a match, Lambatos answered affirmatively. Ibid.

															Second, the prosecutor asked whether Lambatos
had in-dependently “compare[d the DNA profile that Cellmark had
derived from] the semen that had been identified . . .
from the vaginal swabs of [the victim] to the male DNA profile
[found in the database] that had been [derived] . . .
from the blood of Sandy Williams.” Ibid. Lambatos again answered
affirmatively. Ibid.

															Third, the prosecutor asked whether, in
Lambatos’ ex-pert opinion, the DNA profile derived from the semen
identified in the vaginal swabs of the victim was “a match to Sandy
Williams.” Id., at 58. Lambatos again answered affirmatively.
Ibid.

															The Confrontation Clause problem lies in the
fact that Lambatos did not have personal knowledge that the male
DNA profile that Cellmark said was derived from the crime victim’s
vaginal swab sample was in fact correctly derived from that sample.
And no Cellmark expert testified that it was true. Rather, she
simply relied for her knowledge of the fact upon Cellmark’s report.
And the defendant Williams had no opportunity to cross-examine the
individual or individuals who produced that report.

															In its first conclusion, the plurality explains
why it finds that admission of Lambatos’ testimony nonetheless did
not violate the Confrontation Clause. That Clause concerns
out-of-court statements admitted for their truth. Ante, at 15–16.
Lambatos’ testimony did not introduce the Cellmark report (which
other circumstantial evidence supported) for its truth. Ante, at
16–21. Rather, Lam-batos used the Cellmark report only to indicate
the underlying factual information upon which she based her
independent expert opinion. Ibid. Under well-established principles
of evidence, experts may rely on otherwise inadmissible
out-of-court statements as a basis for forming an expert opinion if
they are of a kind that experts in the field normally rely upon.
See Fed. Rule Evid. 703; Ill. Rule Evid. 703. Nor need the
prosecution enter those out-of-court statements into evidence for
their truth. That, the Illinois courts held, is just what took
place here. Ante, at 9–10.

															The dissent would abandon this well-established
rule. It would not permit Lambatos to offer an expert opinion in
reliance on the Cellmark report unless the prosecution also
produces one or more experts who wrote or otherwise produced the
report. I am willing to accept the dissent’s characterization of
the present rule as artificial, see post, at 15–17 (opinion of
Kagan, J.), but I am not certain that the dissent has produced a
workable alternative, see Bullcoming, supra, at ___ (Kennedy, J.,
dissenting) (slip op., at 7) (expressing similar view).

															Once one abandons the traditional rule, there
would seem often to be no logical stopping place between requiring
the prosecution to call as a witness one of the labora-tory experts
who worked on the matter and requiring the prosecution to call all
of the laboratory experts who did so. Experts—especially laboratory
experts—regularly rely on the technical statements and results of
other experts to form their own opinions. The reality of the matter
is that the introduction of a laboratory report involves layer upon
layer of technical statements (express or implied) made by one
expert and relied upon by another. Hence my general question: How
does the Confrontation Clause apply to crime laboratory reports and
underlying technical statements made by laboratory technicians?

															B

															The general question is not easy to answer.
The California case described at the outset of the dissenting
opinion helps to illustrate the difficulty. In that example,
Cellmark, the very laboratory involved in this case, tested a DNA
sample taken from the crime scene. A laboratory analyst, relying
upon a report the laboratory had prepared, initially stated (at a
pretrial hearing about admissibil- ity) that the laboratory had
found that the crime-scene DNA sample matched a sample of the
defendant’s DNA. But during the hearing and after reviewing the
labor-atory’s notes, the laboratory analyst realized that the
written report was mistaken. In fact, the testing showed only that
the crime-scene DNA matched a sample of the victim’s DNA, not the
defendant’s DNA. At some point during the writing of the report,
someone, perhaps the testifying analyst herself, must have misread
the proper original sample labeling. Upon discovering the error,
the analyst corrected her testimony.

															The example is useful, not simply because as
adapted it might show the importance of cross-examination (an
importance no one doubts), but also because it can reveal the
nature of the more general question before us. When the laboratory
in the example received the DNA samples, it labeled them properly.
The laboratory’s final report mixed up the labels. Any one of many
different technicians could be responsible for an error like that.
And the testifying analyst might not have reviewed the underlying
notes and caught the error during direct examination (or for that
matter, during cross-examination).

															Adapting the example slightly, assume that the
admissibility of the initial laboratory report into trial had been
directly at issue. Who should the prosecution have had to call to
testify? Only the analyst who signed the report noting the match?
What if the analyst who made the match knew nothing about either
the laboratory’s underlying procedures or the specific tests run in
the particular case? Should the prosecution then have had to call
all potentially involved laboratory technicians to testify? Six to
twelve or more technicians could have been involved. (See Appendix,
infra, which lists typically relevant laboratory procedures.) Some
or all of the words spoken or written by each technician out of
court might well have constituted relevant statements offered for
their truth and reasonably relied on by a supervisor or analyst
writing the laboratory report. Indeed, petitioner’s amici argue
that the technicians at each stage of the process should be subject
to cross-examination. See Brief for Innocence Network as Amicus
Curiae 13–23 (hereinafter Innocence Network Brief).

															And as is true of many hearsay statements that
fall within any of the 20 or more hearsay exceptions,
cross-examination could sometimes significantly help to elicit the
truth. See Fed. Rule Evid. 803 (listing 24 hearsay exceptions). The
Confrontation Clause as interpreted in Crawford recognizes, as a
limitation upon a pure “testimonial statement” requirement,
circumstances where the defendant had an adequate “prior
opportunity to cross-examine.” 541 U. S., at 59. To what
extent might the “testimonial statements” requirement embody one or
more (or modified versions) of these traditional hearsay exceptions
as well?

															Lower courts and treatise writers have
recognized the problem. And they have come up with a variety of
solutions. The New Wigmore, for example, lists several nonexclusive
approaches to when testifying experts may rely on testing results
or reports by nontestifying experts (i.e., DNA technicians or
analysts), including: (1) “the dominant approach,” which is simply
to determine the need to testify by looking “the quality of the
nontestifying expert’s report, the testifying expert’s involvement
in the process, and the consequent ability of the testifying expert
to use independent judgment and interpretive skill”; (2) permitting
“a substitute expert to testify about forensic science results only
when the first expert is unavailable” (irrespective of the lack of
opportunity to cross-examine the first expert, cf. Crawford, supra,
at 59); (3) permitting “a substitute expert” to testify if “the
original test was documented in a thorough way that permits the
substitute expert to evaluate, assess, and interpret it”; (4)
permitting a DNA analyst to introduce DNA test results at trial
without having “personally perform[ed] every specific aspect of
each DNA test in question, provided the analyst was present during
the critical stages of the test, is familiar with the process and
the laboratory protocol involved, reviews the results in proximity
to the test, and either initials or signs the final report
outlining the results”; (5) permitting the introduction of a crime
laboratory DNA report without the testimony of a technician where
the “testing in its pre-liminary stages” only “requires the
technician simply to perform largely mechanical or ministerial
tasks . . . absent some reason to believe there was error
or falsification”; and (6) permitting introduction of the report
without requiring the technicians to testify where there is a
showing of “genuine unavailability.” See D. Kaye, D. Bernstein,
& J. Mnookin, The New Wigmore: Expert Evidence, §§4.10.2,
4.10.3, pp. 202, 204, 206 (2d ed. 2010) (internal quotation marks
and footnote omitted); id., §4.11.6, at 24 (Supp. 2012).

															Some of these approaches seem more readily
compatible with Crawford than others. Some seem more easily
considered by a rules committee (or by state courts) than by this
Court. Nonetheless, all assume some kind of Crawford boundary—some
kind of limitation upon the scope of its application—though they
reflect different views as to just how and when that might be
done.

															Answering the underlying general question just
discussed, and doing so soon, is important. Trial judges in both
federal and state courts apply and interpret hearsay rules as part
of their daily trial work. The trial of criminal cases makes up a
large portion of that work. And laboratory reports frequently
constitute a portion of the evidence in ordinary criminal trials.
Obviously, judges, prosecutors, and defense lawyers have to know,
in as definitive a form as possible, what the Constitution requires
so that they can try their cases accordingly.

															The several different opinions filed today
embody sev-eral serious, but different, approaches to the difficult
gen-eral question. Yet none fully deals with the underlying
question as to how, after Crawford, Confrontation Clause
“testimonial statement” requirements apply to crime lab-oratory
reports. Nor can I find a general answer in Melendez-Diaz or
Bullcoming. While, as a matter of pure logic, one might use those
cases to answer a narrowed version of the question presented here,
see post, at 7–8 (Kagan, J., dissenting), those cases do not fully
con- sider the broader evidentiary problem presented. I
consequently find the dissent’s response, “Been there, done that,”
unsatisfactory. See post, at 21.

															Under these circumstances, I would have this
case reargued. I would request the parties and amici to focus
specifically upon the broader “limits” question. And I would permit
them to discuss, not only the possible implications of our earlier
post-Crawford opinions, but also any necessary modifications of
statements made in the opinions of those earlier cases.

															II

															In the absence of reargument, I adhere to the
dissenting view set forth in Melendez-Diaz and Bullcoming, under
which the Cellmark report would not be considered “testimonial” and
barred by the Confrontation Clause. See also ante, at 28–33
(setting forth similar conclusion). That view understands the
Confrontation Clause as interpreted in Crawford to bar the
admission of “[t]estimonial” statements made out of court unless
the declarant is unavail-able and the defendant had a prior
opportunity to cross-examine. 541 U. S., at 59 (emphasis
added). It also understands the word “testimonial” as having outer
limits and Crawford as describing a constitutional heartland. And
that view would leave the States with constitutional leeway to
maintain traditional expert testimony rules as well as hearsay
exceptions where there are strong reasons for doing so and
Crawford’s basic rationale does not apply.

															In particular, the States could create an
exception that presumptively would allow introduction of DNA
reports from accredited crime laboratories. The defendant would
remain free to call laboratory technicians as witnesses. Were there
significant reason to question a laboratory’s technical competence
or its neutrality, the presumptive exception would disappear,
thereby requiring the prosecution to produce any relevant technical
witnesses. Such an exception would lie outside Crawford’s
constitutional limits.

															Consider the report before us. Cellmark’s DNA
report embodies technical or professional data, observations, and
judgments; the employees who contributed to the report’s findings
were professional analysts working on technical matters at a
certified laboratory; and the employees operated behind a veil of
ignorance that likely prevented them from knowing the identity of
the defendant in this case. Statements of this kind fall within a
hearsay exception that has constituted an important part of the law
of evidence for decades. See Fed. Rule Evid. 803(6) (“Records of
Regularly Conducted Activity”); 2 J. Wigmore, Evidence §§1517–1533,
pp. 1878–1899 (1904) (“Regular Entries”). And for somewhat similar
reasons, I believe that such statements also presumptively fall
outside the category of “testimonial” statements that the
Confrontation Clause makes inadmissible.

															As the plurality points out, ante, at 28–33, the
introduction of statements of this kind does not risk creating the
“principal evil at which the Confrontation Clause was directed.”
Crawford, 541 U. S., at 50. That evil consists of the
pre-Constitution practice of using “ex parte examinations as
evidence against the accused.” Ibid. Sir Walter Raleigh’s case
illustrates the point. State authorities questioned Lord Cobham,
the key witness against Raleigh, outside his presence. They then
used those testimonial statements in court against Raleigh. And
when Raleigh asked to face and to challenge his accuser, he was
denied that opportunity. See id., at 44.

															The Confrontation Clause prohibits the use of
this kind of evidence because allowing it would deprive a defendant
of the ability to cross-examine the witness. Id., at 61–62; Mattox
v. United States, 156 U.S.
237 –243 (1895). That deprivation would prevent a defendant
from confronting the witness. And it would thereby prevent a
defendant from probing the witness’ perception, memory, narration,
and sincerity. See, e.g., 2 K. Broun et al., McCormick on
Evidence §245, p. 125 (6th ed. 2006); E. Morgan, Some Problems of
Proof Under the Anglo-American System of Litigation 119–127 (1956);
30 C. Wright & K. Graham, Federal Practice and Procedure §6324,
pp. 44–49 (1997); see also M. Hale, History of the Common Law of
England 258 (1713) (explaining virtues of confronting witness); 3
W. Blackstone, Commentaries on the Laws of England 373 (1768)
(same). But the need for cross-examination is considerably
diminished when the out-of-court statement was made by an
accredited laboratory employee operating at a remove from the
investigation in the ordinary course of professional work.

															For one thing, as the hearsay exception itself
reflects, alternative features of such situations help to guarantee
its accuracy. An accredited laboratory must satisfy
well-established professional guidelines that seek to ensure the
scientific reliability of the laboratory’s results. App. 59–60, 74,
86–87; see Brief for National District Attorneys Assn. et al.
as Amici Curiae 25, n. 5 (hereinafter NDAA Brief) (noting that
the standards date back 30 years); Giannelli, Regulating Crime
Laboratories: The Impact of DNA Evidence, 15 J. L. & Pol’y
59, 72–76 (2007). For example, forensic DNA testing laboratories
permitted to access the FBI’s Combined DNA Index System must adhere
to standards governing, among other things, the organization and
management of the laboratory; education, training, and experience
requirements for laboratory personnel; the laboratory’s physical
facilities and security measures; control of physical evidence;
validation of testing methodologies; procedures for analyzing
samples, including the reagents and controls that are used in the
testing process; equipment calibration and maintenance;
documentation of the process used to test each sample handled by
the laboratory; technical and administrative review of every case
file; proficiency testing of laboratory; personnel; corrective
action that addresses any discrepancies in proficiency tests and
casework analysis; internal and external audits of the laboratory;
environmental health and safety; and outsourcing of testing to
vendor laboratories. See Brief for New York County District
Attorney’s Office et al. as Amici Curiae 4, n. 4
(hereinafter NY County DAO Brief); see also App. to NY County DAO
Brief A22–A49.

															These standards are not foolproof. Nor are they
always properly applied. It is not difficult to find instances in
which laboratory procedures have been abused. See, e.g., Innocence
Network Brief 6–11; App. to Brief for Public Defender Service for
the District of Columbia et al. as Amici Curiae 1a–12a; cf.
Giannelli, The Abuse of Scientific Evidence in Criminal Cases: The
Need for Independent Crime Laboratories, 4 Va. J. Soc. Pol’y &
L. 439 (1997). Moreover, DNA testing itself has exonerated some
defendants who previously had been convicted in part upon the basis
of testimony by laboratory experts. See Melendez-Diaz v.
Massachusetts, 557 U. S., at 319 (citing Garrett &
Neufeld, Invalid Forensic Science Testimony and Wrongful
Convictions, 95 Va. L. Rev. 1 (2009)).

															But if accreditation did not prevent admission
of faulty evidence in some of those cases, neither did
cross-examination. In the wrongful-conviction cases to which this
Court has previously referred, the forensic experts all testified
in court and were available for cross-examination. Sklansky,
Hearsay’s Last Hurrah, 2009 S. Ct. Rev. 1, 72–73 (cited study
“did not identify any cases in which hearsay from forensic analysts
contributed to the conviction of innocent defendants”); see Garrett
& Neufeld, supra, at 10–12, 84, 89 (noting that
cross-examination was rarely effective); see also Murphy, The New
Forensics: Criminal Justice, False Certainty, and the Second
Generation of Scientific Evidence, 95 Cal. L. Rev. 721,
785–786 (2007) (suggesting need for greater reliance upon
accreditation and oversight of accredited laboratories); Sklansky,
supra, at 74 (same). Similarly, the role of cross-examination is
ambiguous in the laboratory example that the dissent describes. See
post, at 1–2. (Apparently, the report’s error came to light and was
corrected after cross-examination had concluded, see Thompson,
Taroni, & Aitken, Author’s Response, 49 J. Forensic Sci. 1202
(2003), and in any event all parties had received the correctly
labeled underlying laboratory data, see Clarke, Commentary, id., at
1201).

															For another thing, the fact that the laboratory
testing takes place behind a veil of ignorance makes it unlikely
that a particular researcher has a defendant-related motive to
behave dishonestly, say, to misrepresent a step in an analysis or
otherwise to misreport testing results. Cf. Michigan v. Bryant, 562
U. S. ___, ___ (2011) (slip op., at 14) (discussing the
“prospect of fabrication” as a factor in whether the Confrontation
Clause requires statements “to be subject to the crucible of
cross-examination”). The laboratory here, for example, did not know
whether its test results might help to incriminate a particular
defendant. Ante, at 32–33; cf. Melendez-Diaz, supra, at 310–311;
Bullcoming, 564 U. S., at ___ (slip op., at 14).

															Further, the statements at issue, like those of
many laboratory analysts, do not easily fit within the linguistic
scope of the term “testimonial statement” as we have used that term
in our earlier cases. As the plurality notes, in every
post-Crawford case in which the Court has found a Confrontation
Clause violation, the statement at issue had the primary purpose of
accusing a targeted individual. Ante, at 29–31; see, e.g., Davis v.
Washington, 547 U.S.
813 , 822 (2006) (“primary purpose . . . is to
establish or prove past events potentially relevant to later
criminal prosecution”); Bryant, supra, at ___–___ (slip op., at
11–12) (“primary purpose of creating an out-of-court substitute for
trial testimony”). The declarant was essentially an adverse witness
making an accusatory, testimonial statement—implicating the core
concerns of the Lord Cobham-type affidavits. But here the DNA
report sought, not to accuse petitioner, but instead to generate
objectively a profile of a then-unknown suspect’s DNA from the
semen he left in committing the crime. See ante, at 31–33.

															Finally, to bar admission of the out-of-court
records at issue here could undermine, not fortify, the accuracy of
factfinding at a criminal trial. Such a precedent could bar the
admission of other reliable case-specific technical information
such as, say, autopsy reports. Autopsies, like the DNA report in
this case, are often conducted when it is not yet clear whether
there is a particular suspect or whether the facts found in the
autopsy will ultimately prove relevant in a criminal trial.
Autopsies are typically conducted soon after death. And when, say,
a victim’s body has decomposed, repetition of the autopsy may not
be possible. What is to happen if the medical examiner dies before
trial? E.g., State v. Lackey, 280 Kan. 190, 195–196, 120 P.3d 332,
341 (2005); see also People v. Geier, 41 Cal. 4th 555, 601–602, 161
P.3d 104, 136–137 (2007). Is the Confrontation Clause
“ ‘effectively’ ” to function “ ‘as a statute of
limitations for murder’ ”? Melendez-Diaz, supra, at 335
(Kennedy, J., dissenting) (quoting Comment, Toward a Definition of
“Testimonial”: How Autopsy Reports Do Not Embody the Qualities of a
Testimonial Statement, 96 Cal. L. Rev. 1093, 1115 (2008)).

															In general, such a holding could also increase
the risk of convicting the innocent. The New York County District
Attorney’s Office and the New York City Office of the Chief Medical
Examiner tell us that the additional cost and complexity involved
in requiring live testimony from perhaps dozens of ordinary
laboratory technicians who participate in the preparation of a DNA
profile may well force a laboratory “to reduce the amount of DNA
testing it conducts, and force prosecutors to forgo forensic DNA
analysis in cases where it might be highly probative. In the
absence of DNA testing, defendants might well be prosecuted solely
on the basis of eyewitness testimony, the reliability of which is
often questioned.” NY County DAO Brief 10 (citing United States v.
Wade, 388 U.S.
218 , 229 (1967) ); see also NDAA Brief 26 (such a holding “will
also impact the innocent who may wait to be cleared from suspicion
or exonerated from mistaken conviction”). I find this plausible.
But cf. Innocence Network Brief 3. An interpretation of the Clause
that risks greater prosecution reliance upon less reliable evidence
cannot be sound. Cf. Maryland v. Craig, 497
U.S. 836 , 845 (1990) (“The central concern of the Confrontation
Clause is to ensure the reli-ability of the evidence against a
criminal defendant”).

															Consequently, I would consider reports such as
the DNA report before us presumptively to lie outside the perimeter
of the Clause as established by the Court’s precedents. Such a
holding leaves the defendant free to call the laboratory employee
as a witness if the employee is available. Moreover, should the
defendant provide good reason to doubt the laboratory’s competence
or the validity of its accreditation, then the alternative
safeguard of reliability would no longer exist and the Constitution
would entitle defendant to Confrontation Clause protection.
Similarly, should the defendant demonstrate the existence of a
motive to falsify, then the alternative safeguard of honesty would
no longer exist and the Constitution would entitle the defendant to
Confrontation Clause protection. Cf. 2 Wigmore, Evidence §1527, at
1892 (in respect to the business records exception, “there must
have been no motive to misrepresent”). Thus, the defendant would
remain free to show the absence or inadequacy of the alternative
reliability/honesty safeguards, thereby rebutting the pre-sumption
and making the Confrontation Clause applicable. No one has
suggested any such problem in respect to the Cellmark Report at
issue here.

															Because the plurality’s opinion is basically
consistent with the views set forth here, I join that opinion in
full.

															APPENDIX

															This appendix outlines the way that a typical
modern fo-rensic laboratory conducts DNA analysis. See NY County
DAO Brief 7–8; NDAA Brief 22–23; Innocence Network Brief 13–23; see
also Dept. of Justice, Office of the Inspector General, The FBI DNA
Laboratory: A Review of Protocol and Practice Vulnerabilities 6–14
(May 2004), online at
http://www.justice.gov/oig/special/0405/final.pdf (as visited June
14, 2012, and available in Clerk of Court’s case file). The DNA
analysis takes place in three parts, through three different sets
of laboratory experts: (1) a DNA pro-file is derived from the
suspect’s DNA sample, (2) a DNA profile is derived from the
crime-scene DNA sample, and (3) an analyst compares the two
profiles and makes a conclusion.

															As many as six technicians may be involved in
deriving the profile from the suspect’s sample; as many as six more
technicians may be involved in deriving the profile from the
crime-scene sample; and an additional expert may then be required
for the comparative analysis, for a total of about a dozen
different laboratory experts. Each expert may make technical
statements (express or implied) during the DNA analysis process
that are in turn relied upon by other experts. The amici dispute
how many of these experts the Confrontation Clause requires to be
subject to cross-examination. Compare Innocence Network Brief 13–23
with NY County DAO Brief 7–8 and NDAA Brief 22–23. In charting the
three-step process, the appendix first summarizes the laboratory
procedures used to derive a DNA profile and then illustrates
potential statements that technicians may make to explain their
analysis.

															[Graphic omitted; see printed opinion.]

															[Graphic omitted; see printed opinion.]

															[Graphic omitted; see printed opinion.] SUPREME COURT OF THE UNITED STATES

															_________________

															No. 10–8505

															_________________

															SANDY WILLIAMS, PETITIONER v. ILLINOIS

															on writ of certiorari to the supreme court of
illinois

															[June 18, 2012]

															Justice Thomas, concurring in the
judgment.

															I agree with the plurality that the disclosure
of Cellmark’s out-of-court statements through the expert testimony
of Sandra Lambatos did not violate the Confrontation Clause. I
reach this conclusion, however, solely because Cellmark’s
statements lacked the requisite “formality and solemnity” to be
considered “ ‘testimonial’ ” for purposes of the
Confrontation Clause. See Michigan v. Bryant, 562 U. S. ___,
___ (2011) (Thomas, J., concurring in judgment) (slip op., at 1).
As I explain below, I share the dissent’s view of the plurality’s
flawed analysis.

															I

															The threshold question in this case is whether
Cell- mark’s statements were hearsay at all. As the Court has
explained, “[t]he [Confrontation] Clause . . . does not
bar the use of testimonial statements for purposes other than
establishing the truth of the matter asserted.” See Crawford v.
Washington, 541 U.S.
36 , n. 9 (2004) (citing Tennessee v. Street, 471 U.S.
409 , 414 (1985) ). Here, the State of Illinois contends that
Cellmark’s statements—that it successfully derived a male DNA
profile and that the profile came from L. J.’s swabs—were
introduced only to show the basis of Lambatos’ opinion, and not for
their truth. In my view, however, there was no plau- sible reason
for the introduction of Cellmark’s statements other than to
establish their truth.

															A

															Illinois Rule of Evidence 703 (2011) and its
federal counterpart permit an expert to base his opinion on facts
about which he lacks personal knowledge and to disclose those facts
to the trier of fact. Relying on these Rules, the State contends
that the facts on which an expert’s opinion relies are not to be
considered for their truth, but only to explain the basis of his
opinion. See People v. Pasch, 152 Ill. 2d 133 , 176, 604 N.E.2d 294 , 311 (1992) (“By allowing an expert to reveal
the information for this purpose alone, it will undoubtedly aid the
jury in assessing the value of his opinion”); see also Advisory
Committee’s Notes on Fed. Rule Evid. 703, 28 U. S. C.
App., p. 361 (stating that expert basis testimony is
admissible “only for the purpose of assisting the jury in
evaluating an expert’s opinion”). Accordingly, in the State’s view,
the disclosure of expert “basis testimony” does not implicate the
Confrontation Clause.

															I do not think that rules of evidence should so
easily trump a defendant’s confrontation right. To be sure, we
should not “lightly swee[p] away an accepted rule” of federal or
state evidence law, ante, at 2 (internal quotation marks omitted),
when applying the Confrontation Clause. “Rules of limited
admissibility are commonplace in evidence law.” Mnookin, Expert
Evidence and the Confrontation Clause after Crawford v. Washington,
15 J. L. & Pol’y 791, 812 (2007). And, we often presume
that courts and juries follow limiting instructions. See, e.g.,
Street, supra, at 415, n. 6. But we have recognized that
concepts central to the application of the Confrontation Clause are
ultimately matters of federal constitutional law that are not
dictated by state or federal evidentiary rules. See Barber v. Page, 390 U.S.
719 –725 (1968) (defining a constitutional standard for whether
a witness is “unavailable” for purposes of the Confrontation
Clause); see also Ohio v. Roberts, 448 U.S.
56 , 76 (1980) (recognizing that Barber “explored the issue of
constitutional unavailability” (emphasis added)). Likewise, we have
held that limiting in- structions may be insufficient in some
circumstances to protect against violations of the Confrontation
Clause. See Bruton v. United States, 391 U.S.
123 (1968) .

															Of particular importance here, we have made sure
that an out-of-court statement was introduced for a “legitimate,
nonhearsay purpose” before relying on the not-for-its-truth
rationale to dismiss the application of the Confrontation Clause.
See Street, 471 U. S., at 417 (emphasis added). In Street, the
defendant testified that he gave a false confession because police
coerced him into parroting his accomplice’s confession. Id., at
411. On rebuttal, the prosecution introduced the accomplice’s
confession to demonstrate to the jury the ways in which the two
confessions differed. Id., at 411–412. Finding no Confrontation
Clause problem, this Court held that the accomplice’s out-of-court
confession was not introduced for its truth, but only to impeach
the defendant’s version of events. Id., at 413–414. Although the
Court noted that the confession was not hearsay “under traditional
rules of evidence,” id., at 413, the Court did not accept that
nonhearsay label at face value. Instead, the Court thoroughly
examined the use of the out-of-court confession and the efficacy of
a limiting instruction before concluding that the Confrontation
Clause was satisfied “[i]n this context.” Id., at 417.

															Unlike the confession in Street, statements
introduced to explain the basis of an expert’s opinion are not
introduced for a plausible nonhearsay purpose. There is no
meaningful distinction between disclosing an out-of-court statement
so that the factfinder may evaluate the expert’s opinion and
disclosing that statement for its truth. “To use the inadmissible
information in evaluating the expert’s testimony, the jury must
make a preliminary judgment about whether this information is
true.” D. Kaye, D. Bernstein, & J. Mnookin, The New Wigmore: A
Treatise on Evidence: Expert Evidence §4.10.1, p. 196 (2d ed.
2011) (hereinafter Kaye). “If the jury believes that the basis
evidence is true, it will likely also believe that the expert’s
reliance is justified; inversely, if the jury doubts the accuracy
or validity of the basis evidence, it will be skeptical of the
expert’s conclusions.” Ibid. [ 1 ]

															Contrary to the plurality’s suggestion, this
common- sense conclusion is not undermined by any longstand- ing
historical practice exempting expert basis testimony from the
rigors of the Confrontation Clause. Prior to the adoption of the
Federal Rules of Evidence in 1975, an expert could render an
opinion based only on facts that the expert had personally
perceived or facts that the expert learned at trial, either by
listening to the testimony of other witnesses or through a
hypothetical question based on facts in evidence. See Advisory
Committee’s Notes on Fed. Rule Evid. 703, 28 U. S. C.
App., p. 361; 29 C. Wright & V. Gold, Federal Practice and
Procedure §6271, pp. 300–301 (1997) (hereinafter Wright); 1 K.
 Broun et al., McCormick on Evidence §14, p. 86 (6th ed.
2006) (hereinafter Broun); Kaye §4.6, at 156–157. In those
situations, there was little danger that the expert would rely on
testimonial hearsay that was not subject to confrontation because
the expert and the witnesses on whom he relied were present at
trial. It was not until 1975 that the universe of facts upon which
an expert could rely was expanded to include facts of the case that
the expert learned out of court by means other than his own
perception. 1 Broun §14, at 87; Kaye §4.6, at 157. It is the
expert’s disclosure of those facts that raises Confrontation Clause
concerns. [ 2 ]

															B

															Those concerns are fully applicable in this
case. Lambatos opined that petitioner’s DNA profile matched the
male profile derived from L. J.’s vaginal swabs. In reaching
that conclusion, Lambatos relied on Cellmark’s out-of-court
statements that the profile it reported was in fact derived from
L. J.’s swabs, rather than from some other source. Thus, the
validity of Lambatos’ opinion ultimately turned on the truth of
Cellmark’s statements. The plurality’s assertion that Cellmark’s
statements were merely relayed to explain “the assumptions on which
[Lambatos’] opinion rest[ed],” ante, at 3, overlooks that the value
of Lambatos’ testimony depended on the truth of those very
assumptions. [ 3 ]

															It is no answer to say that other nonhearsay
evidence established the basis of the expert’s opinion. Here,
Lambatos disclosed Cellmark’s statements that it generated a male
DNA profile from L. J.’s swabs, but other evidence showed that
L. J.’s swabs contained semen and that the swabs were shipped
to and received from Cellmark. Ante, at 5–6. That evidence did not
render Cellmark’s statements superfluous. Of course, evidence that
Cellmark received L. J.’s swabs and later produced a DNA
profile is some indication that Cellmark in fact generated the
profile from those swabs, rather than from some other source (or
from no source at all). Cf. Melendez-Diaz v. Massachusetts, 557
U.S. 305 , 319 (2009) (citing brief that describes “cases of
documented ‘drylabbing’ where forensic analysts report results of
tests that were never performed,” including DNA tests). But the
only direct evidence to that effect was Cellmark’s statement, which
Lambatos relayed to the factfinder. In any event, the factfinder’s
ability to rely on other evidence to evaluate an expert’s opinion
does not alter the conclusion that basis testimony is admitted for
its truth. The existence of other evidence corroborating the basis
testimony may render any Confrontation Clause violation harmless,
but it does not change the purpose of such testimony and thereby
place it outside of the reach of the Confrontation Clause. [ 4 ] I would thus conclude that
Cellmark’s statements were introduced for their truth.

															C

															The plurality’s contrary conclusion may seem
of little consequence to those who view DNA testing and other forms
of “hard science” as intrinsically reliable. But see Melendez-Diaz,
supra, at 318 (“Forensic evidence is not uniquely immune from the
risk of manipulation”). Today’s holding, however, will reach beyond
scientific evidence to ordinary out-of-court statements. For
example, it is not uncommon for experts to rely on interviews with
third parties in forming their opinions. See, e.g., People v.
Goldstein, 6 N.Y.3d 119, 123–124, 843 N.E.2d 727, 729–730 (2005)
(psychiatrist disclosed statements made by the defendant’s
acquaintances as part of the basis of her opinion that the
defendant was motivated to kill by his feelings of sexual
frustration).

															It is no answer to say that “safeguards” in the
rules of evidence will prevent the abuse of basis testimony. Ante,
at 26. To begin with, courts may be willing to conclude that an
expert is not acting as a “mere condui[t]” for hearsay, ante, at
27, as long as he simply provides some opinion based on that
hearsay. See Brief for Respondent 18, n. 4 (collecting cases).
In addition, the hearsay may be the kind of fact on which experts
in a field reasonably rely. See Fed. Rule Evid. 703; Goldstein,
supra, at 125, 843 N. E. 2d, at 731 (evidence showed that
reputable psychiatrists relied upon third-party interviews in
forming their opinions). Of course, some courts may determine that
hearsay of this sort is not substantially more probative than
prejudicial and therefore should not be disclosed un- der Rule 703.
But that balancing test is no substitute for a constitutional
provision that has already struck the balance in favor of the
accused. See Crawford, 541 U. S., at 61 (“[The Confrontation
Clause] commands, not that evidence be reliable, but that
reliability be assessed in a particular manner: by testing in the
crucible of cross-examination”).

															II

															A

															Having concluded that the statements at issue
here were introduced for their truth, I turn to whether they were
“testimonial” for purposes of the Confrontation Clause. In
Crawford, the Court explained that “[t]he text of the Confrontation
Clause . . . applies to ‘witnesses’ against the
accused—in other words, those who ‘bear testimony.’ ” Id., at
51 (quoting 2 N. Webster, An American Dictionary of the English
Language (1828)). “ ‘Testimony,’ ” in turn, is
“ ‘[a] solemn declaration or affirmation made for the purpose
of establishing or proving some fact.’ ” 541 U. S., at
51. In light of its text, I continue to think that the
Confrontation Clause regulates only the use of statements bearing
“indicia of solemnity.” Davis v. Washington, 547 U.S.
813 –837, 840 (2006) (Thomas, J., concurring in judgment in
part and dissenting in part). This test comports with history
because solemnity marked the practices that the Confrontation
Clause was designed to eliminate, namely, the ex parte
examination of wit- nesses under the English bail and committal
statutes passed during the reign of Queen Mary. See id., at 835;
Bryant, 562 U. S., at ___ (Thomas, J., concurring in judgment)
(slip op., at 1); Crawford, supra, at 43–45. Accordingly, I have
concluded that the Confrontation Clause reaches “ ‘formalized
testimonial materials,’ ” such as depositions, affidavits, and
prior testimony, or statements resulting from “ ‘formalized
dialogue,’ ” such as custodial interrogation. Bryant, supra,
at ___ (slip op., at 2); see also Davis, supra, at 836–837. [ 5 ]

															Applying these principles, I conclude that
Cellmark’s report is not a statement by a “witnes[s]” within the
meaning of the Confrontation Clause. The Cellmark report lacks the
solemnity of an affidavit or deposition, for it is neither a sworn
nor a certified declaration of fact. Nowhere does the report attest
that its statements accurately reflect the DNA testing processes
used or the results ob- tained. See Report of Laboratory
Examination, Lodging of Petitioner. The report is signed by two
“reviewers,” but they neither purport to have performed the DNA
testing nor certify the accuracy of those who did. See ibid. And,
although the report was produced at the request of law enforcement,
it was not the product of any sort of formalized dialogue
resembling custodial interrogation.

															The Cellmark report is distinguishable from the
laboratory reports that we determined were testimonial in
Melendez-Diaz, 557 U.S.
305 , and in Bullcoming v. New Mexico, 564 U. S. ___
(2011). In Melendez-Diaz, the reports in question were “sworn to
before a notary public by [the] analysts” who tested a substance
for cocaine. 557 U. S., at 308. In Bullcoming, the report,
though unsworn, included a “Certificate of Analyst” signed by the
forensic analyst who tested the defendant’s blood sample. 564
U. S., at ___ (slip op., at 3). The analyst “affirmed that
‘[t]he seal of th[e] sample was received intact and broken in the
laboratory,’ that ‘the statements in [the analyst’s block of the
report] are correct,’ and that he had ‘followed the procedures set
out on the reverse of th[e] report.’ ” Ibid.

															The dissent insists that the Bullcoming report
and Cellmark’s report are equally formal, separated only by such
“minutia” as the fact that Cellmark’s report “is not labeled a
‘certificate.’ ” Post, at 22–23 (opinion of Kagan, J.). To the
contrary, what distinguishes the two is that Cellmark’s report, in
substance, certifies nothing. See su- pra, at 9. That distinction
is constitutionally significant because the scope of the
confrontation right is properly limited to extrajudicial statements
similar in solemnity to the Marian examination practices that the
Confrontation Clause was designed to prevent. See Davis, supra, at
835–836 (opinion of Thomas, J.). By certifying the truth of the
analyst’s representations, the unsworn Bullcoming report bore “a
‘striking resemblance,’  ” 547 U. S., at 837 (quot- ing
Crawford, 541 U. S., at 52), to the Marian practice in which
magistrates examined witnesses, typically on oath, and “certif[ied]
the results to the court.” Id., at 44. And, in Melendez-Diaz, we
observed that “ ‘certificates’ are functionally identical to
live, in-court testimony, doing precisely what a witness does on
direct examination.” 557 U. S., at 310–311. Cellmark’s report
is marked by no such indicia of solemnity.

															Contrary to the dissent’s suggestion,
acknowledging that the Confrontation Clause is implicated only by
formalized statements that are characterized by solemnity will not
result in a prosecutorial conspiracy to elude confrontation by
using only informal extrajudicial statements against an accused. As
I have previously noted, the Confrontation Clause reaches bad-faith
attempts to evade the formalized process. See supra, at 9,
n. 5 (quoting Davis, 547 U. S., at 838). Moreover, the
prosecution’s use of informal statements comes at a price. As the
dissent recognizes, such statements are “less reliable” than
formalized statements, post, at 24, and therefore less persuasive
to the factfinder. Cf. post, at 21–22, n. 6 (arguing that
prosecutors are unlikely to “forgo DNA evidence in favor of less
reliable eyewitness testimony” simply because the defendant is
entitled to confront the DNA analyst). But, even assuming that the
dissent accurately predicts an upswing in the use of “less
reliable” informal statements, that result does not “turn the
Confrontation Clause upside down.” Post, at 24. The Confrontation
Clause does not require that evidence be reliable, Crawford, supra,
at 61, but that the reliability of a specific “class of testimonial
statements”—formalized statements bearing indicia of solemnity—be
assessed through cross-examination. See Melendez-Diaz, 557
U. S., at 309–310.

															B

															Rather than apply the foregoing principles,
the plurality invokes its “primary purpose” test. The original
formulation of that test asked whether the primary purpose of an
extrajudicial statement was “to establish or prove past events
potentially relevant to later criminal prosecution.” Davis, supra,
at 822. I agree that, for a statement to be testimonial within the
meaning of the Confrontation Clause, the declarant must primarily
intend to establish some fact with the understanding that his
statement may be used in a criminal prosecution. See Bryant, 562
U. S., at ___ (Scalia, J., dissenting) (slip op., at 2–3). But
this necessary criterion is not sufficient, for it sweeps into the
ambit of the Confrontation Clause statements that lack formality
and solemnity and is thus “disconnected from history.” Davis,
supra, at 838–842 (opinion concurring in judgment in part and
dissenting in part); Bryant, supra, at ___ (opinion concurring in
judgment) (slip op., at 1). In addition, a primary purpose inquiry
divorced from solemnity is unworkable in practice. Davis, supra, at
839; Bryant, supra, at ___ (slip op., at 1). Statements to police
are often made both to resolve an ongoing emergency and to
establish facts about a crime for potential prosecution. The
primary purpose test gives courts no principled way to assign
primacy to one of those purposes. Davis, supra, at 839. The
solemnity requirement is not only true to the text and history of
the Confrontation Clause, but goes a long way toward resolving that
practical difficulty. If a statement bears the formality and
solemnity necessary to come within the scope of the Clause, it is
highly unlikely that the statement was primarily made to end an
ongoing emergency.

															The shortcomings of the original primary purpose
test pale in comparison, however, to those plaguing the
reformulated version that the plurality suggests today. The new
primary purpose test asks whether an out-of-court statement has
“the primary purpose of accusing a targeted individual of engaging
in criminal conduct.” Ante, at 29. That test lacks any grounding in
constitutional text, in history, or in logic.

															The new test first requires that an out-of-court
statement be made “for the purpose of proving the guilt of a
particular criminal defendant.” Ante, at 30 (emphasis added). Under
this formulation, statements made “before any suspect was
identified” are beyond the scope of the Confrontation Clause. See
ante, at 3. There is no textual justification, however, for
limiting the confrontation right to statements made after the
accused’s identity became known. To be sure, the Sixth Amendment
right to confrontation attaches “[i]n . . . criminal
prosecutions,” at which time the accused has been identified and
apprehended. But the text of the Confrontation Clause does not
constrain the time at which one becomes a “witnes[s].” Indeed, we
have previously held that a declarant may become a “witnes[s]”
before the accused’s prosecution. See Crawford, 541 U. S., at
50–51 (rejecting the view that the Confrontation Clause applies
only to in-court testimony).

															Historical practice confirms that a declarant
could become a “witnes[s]” before the accused’s identity was known.
As previously noted, the confrontation right was a response to ex
parte examinations of witnesses in 16th-century England. Such
examinations often occurred after an accused was arrested or bound
over for trial, but some examinations occurred while the accused
remained “unknown or fugitive.” J. Langbein, Prosecuting Crime in
the Renaissance 90 (1974) (describing examples, including the
deposition of a victim who was swindled out of 20 shillings by a
“ ‘cunning man’ ”); see also 1 J. Stephen, A History of
the Criminal Law of England 217–218 (1883) (describ- ing the sworn
examinations of witnesses by coroners, who were charged with
investigating suspicious deaths by asking local citizens if they
knew “who [was] culpable either of the act or of the force”
(internal quotation marks omitted)).

															There is also little logical justification for
the plurality’s rule. The plurality characterizes Cellmark’s report
as a statement elicited by police and made by Cellmark not “to
accuse petitioner or to create evidence for use at trial,” but
rather to resolve the ongoing emergency posed by “a dangerous
rapist who was still at large.” Ante, at 31. But, as I have
explained, that distinction is unworkable in light of the mixed
purposes that often underlie statements to the police. See supra,
at 12. The difficulty is only compounded by the plurality’s attempt
to merge the purposes of both the police and the declarant. See
ante, at 29; Bryant, supra, at ___–___ (majority opinion) (slip
op., at 20–23).

															But if one purpose must prevail, here it should
surely be the evidentiary one, whether viewed from the perspective
of the police, Cellmark, or both. The police confirmed the presence
of semen on L. J.’s vaginal swabs on February 15, 2000, placed
the swabs in a freezer, and waited until November 28, 2000, to ship
them to Cellmark. App. 30–34, 51–52. Cellmark, in turn, did not
send its report to the police until April 3, 2001, id., at 54, over
a year after L. J.’s rape. Given this timeline, it strains
credulity to assert that the police and Cellmark were primarily
concerned with the exigencies of an ongoing emergency, rather than
with producing evidence in the ordinary course.

															In addition to requiring that an out-of-court
statement “targe[t]” a particular accused, the plurality’s new
primary purpose test also considers whether the statement is so
“inherently inculpatory,” ante, at 3, that the declarant should
have known that his statement would incriminate the accused. In
this case, the plurality asserts that “[t]he technicians who
prepare a DNA profile generally have no way of knowing whether it
will turn out to be incriminating or exonerating—or both,” ante, at
32, and thus “no one at Cellmark could have possibly known that the
profile that it produced would turn out to inculpate petitioner,”
ante, at 31.

															Again, there is no textual justification for
this limitation on the scope of the Confrontation Clause. In
Melendez-Diaz, we held that “[t]he text of the [Sixth] Amendment
contemplates two classes of witnesses—those against the defendant
and those in his favor.” 557 U. S., at 313–314. We emphasized
that “there is not a third category of witnesses, helpful to the
prosecution, but somehow immune from confrontation.” Id., at 314.
Thus, the distinction between those who make “inherently
inculpatory” statements and those who make other statements that
are merely “helpful to the prosecution” has no foundation in the
text of the Amendment.

															It is also contrary to history. The 16th-century
Marian statutes instructed magistrates to transcribe any
information by witnesses that “ ‘shall be material to prove
the felony.’ ” See, e.g., 1 Stephen, supra, at 219 (quoting 1
& 2 Phil. & Mary, ch. 13 (1554)). Magistrates in the 17th
and 18th centuries were also advised by practice manuals to take
the ex parte examination of a witness even if his evi- dence
was “weak” or the witness was “unable to inform any material thing
against” an accused. J. Beattie, Crime and the Courts in England:
1660–1800, p. 272 (1986) (internal quotation marks omitted). Thus,
neither law nor practice limited ex parte examinations to
those witnesses who made “inherently inculpatory” statements.

															This requirement also makes little sense. A
statement that is not facially inculpatory may turn out to be
highly probative of a defendant’s guilt when considered with other
evidence. Recognizing this point, we previously rejected the view
that a witness is not subject to confrontation if his testimony is
“inculpatory only when taken together with other evidence.”
Melendez-Diaz, supra, at 313. I see no justification for reviving
that discredited approach, and the plurality offers none. [ 6 ]

															*  *  *

															Respondent and its amici have emphasized the
economic and logistical burdens that would be visited upon States
should every analyst who reports DNA results be required to testify
at trial. See, e.g., ante, at 32 (citing brief stating that some
crime labs use up to 12 technicians when testing a DNA sample).
These burdens are largely the product of a primary purpose test
that reaches out-of-court statements well beyond the historical
scope of the Confrontation Clause and thus sweeps in a broad range
of sources on which modern experts regularly rely. The proper
solution to this problem is not to carve out a Confrontation Clause
exception for expert testimony that is rooted only in legal
fiction. See ante, at 3. Nor is it to create a new primary purpose
test that ensures that DNA evidence is treated differently. See
ibid. Rather, the solution is to adopt a reading of the
Confrontation Clause that respects its historically limited
application to a narrow class of statements bearing indicia of
solemnity. In forgoing that approach, today’s decision diminishes
the Confrontation Clause’s protection in cases where experts convey
the contents of solemn, formalized statements to explain the bases
for their opinions. These are the very cases in which the accused
should “enjoy the right . . . to be confronted with the
witnesses against him.” Notes 1 The plurality relies
heavily on the fact that this case involved a bench trial,
emphasizing that a judge sitting as factfinder is presumed—more so
than a jury—to “understand the limited reason for the disclosure”
of basis testimony and to “not rely on that information for any
improper purpose.” Ante, at 15. Even accepting that presumption,
the point is not that the factfinder is unable to understand the
restricted purpose for basis testimony. Instead, the point is that
the purport-edly “limited reason” for such testimony—to aid the
factfinder in evaluating the expert’s opinion—necessarily entails
an evaluation of whether the basis testimony is true. 2 In its discussion of
history, the plurality relies on Beckwith v. Sydebotham, 1 Camp.
116, 170 Eng. Rep. 897 (K. B. 1807). In that case, experts were
asked to render opinions on a ship’s seaworthiness based on facts
read into court from the sworn ex parte deposition of a
witness who purported to have seen the ship’s deficiencies. To be
sure, Beckwith involved expert reliance on testimonial hearsay. But
Beckwith was an English case decided after the ratification of the
Confrontation Clause, and this form of expert testimony does not
appear to have been a common feature of early American evidentiary
practice. See 29 Wright §6271, at 300–301; 1 Broun §14, at
86–87; Kaye §4.6, at 156–157. 3 Cellmark’s statements
were not introduced for the nonhearsay purpose of showing their
effect on Lambatos—i.e., to explain what prompted her to search the
DNA database for a match. See, e.g., 30B M. Graham, Federal
Practice and Procedure §7034.1, pp. 521–529 (interim ed. 2011)
(noting that out-of-court statements introduced for their effect on
listener do not implicate the Confrontation Clause). The statements
that Lambatos conveyed went well beyond what was necessary to
explain why she performed the search. Lambatos did not merely
disclose that she received a DNA profile from Cellmark. Rather, she
further disclosed Cellmark’s statements that the profile was “male”
and that it was “found in semen from the vaginal swabs of
[L. J.].” App. 56. Those facts had nothing to do with her
decision to conduct a search. They were introduced for their
truth. 4 The plurality concludes
that the Confrontation Clause would notbe implicated here “even if
the record did not contain any [other] evi-dence that could
rationally support a finding that Cellmark produced a
scientifically reliable DNA profile based on L. J.’s vaginal
swab.” Ante, at 22. But, far from establishing a “legitimate”
nonhearsay purpose for Cellmark’s statements, Tennessee v. Street, 471 U.S.
409 , 417 (1985) , a complete lack of other evidence tending to
prove the facts conveyed by Cellmark’s statements would completely
refute the not-for-its-truth rationale. The trial court, in
announcing its verdict, expressly concluded that petitioner’s DNA
matched the “DNA . . . in the semen recovered from the
victim’s vagina.” 4 R. JJJ151. Absent other evidence, it would have
been impossible for the trial court to reach that conclusion
without relying on the truth of Cellmark’s statement that its test
results were based on the semen from L. J.’s
swabs. 5 In addition, I have
stated that, because the Confrontation Clause “sought to regulate
prosecutorial abuse occurring through use of ex parte
statements,” it “also reaches the use of technically informal
statements when used to evade the formalized process.” Davis, 547
U. S., at 838 (opinion concurring in judgment in part and
dissenting in part). But, in this case, there is no indication that
Cellmark’s statements were offered “in order to evade
confrontation.” Id., at 840. 6 The plurality states that
its test “will not prejudice any defendant who really wishes to
probe the reliability” of out-of-court statements introduced in his
case because the person or persons who made the statements “may
always be subpoenaed by the defense and questioned at trial.” Ante,
at 4. Melendez-Diaz rejected this reasoning as well, holding that
the defendant’s subpoena power “is no substitute for the right of
confrontation.” 557 U. S., at 324. SUPREME COURT OF THE UNITED STATES

															_________________

															No. 10–8505

															_________________

															SANDY WILLIAMS, PETITIONER v. ILLINOIS

															on writ of certiorari to the supreme court of
illinois

															[June 18, 2012]

															Justice Kagan, with whom Justice Scalia,
Justice Ginsburg, and Justice Sotomayor join, dissenting.

															Some years ago, the State of California
prosecuted a man named John Kocak for rape. At a preliminary
hearing, the State presented testimony from an analyst at the
Cellmark Diagnostics Laboratory—the same facility used to generate
DNA evidence in this case. The analyst had extracted DNA from a
bloody sweatshirt found at the crime scene and then compared it to
two control samples—one from Kocak and one from the victim. The
analyst’s report identified a single match: As she explained on
direct examination, the DNA found on the sweatshirt belonged to
Kocak. But after undergoing cross-examination, the analyst realized
she had made a mortifying error. She took the stand again, but this
time to admit that the report listed the victim’s control sample as
coming from Kocak, and Kocak’s as coming from the victim. So the
DNA on the sweatshirt matched not Kocak, but the victim herself.
See Tr. in No. SCD110465 (Super. Ct. San Diego Cty., Cal., Nov. 17,
1995), pp. 3–4 (“I’m a little hysterical right now, but I
think . . . the two names should be switched”), online at
http://www.nlada.org/forensics/for_
lib/Documents/1037341561.0/JohnIvanKocak.pdf (as vis- ited June 15,
2012, and available in Clerk of Court’s case file). In trying
Kocak, the State would have to look elsewhere for its evidence.

															Our Constitution contains a mechanism for
catching such errors—the Sixth Amendment’s Confrontation Clause.
That Clause, and the Court’s recent cases interpreting it, require
that testimony against a criminal defendant be subject to
cross-examination. And that command applies with full force to
forensic evidence of the kind involved in both the Kocak case and
this one. In two decisions issued in the last three years, this
Court held that if a prosecutor wants to introduce the results of
forensic testing into evidence, he must afford the defendant an
opportunity to cross-examine an analyst responsible for the test.
Forensic evidence is reliable only when properly produced, and the
Confrontation Clause prescribes a particular method for determining
whether that has happened. The Kocak incident illustrates how the
Clause is designed to work: Once confronted, the analyst discovered
and disclosed the error she had made. That error would probably not
have come to light if the prosecutor had merely admitted the report
into evidence or asked a third party to present its findings. Hence
the genius of an 18th-century device as applied to 21st-century
evidence: Cross-examination of the analyst is especially likely to
reveal whether vials have been switched, samples contaminated,
tests incompetently run, or results inaccurately recorded.

															Under our Confrontation Clause precedents, this
is an open-and-shut case. The State of Illinois prosecuted Sandy
Williams for rape based in part on a DNA profile created in
Cellmark’s laboratory. Yet the State did not give Williams a chance
to question the analyst who produced that evidence. Instead, the
prosecution introduced the results of Cellmark’s testing through an
expert witness who had no idea how they were generated. That
approach—no less (perhaps more) than the confrontation-free methods
of presenting forensic evidence we have formerly banned—deprived
Williams of his Sixth Amendment right to “confron[t]
. . . the witnesses against him.”

															The Court today disagrees, though it cannot
settle on a reason why. Justice Alito, joined by three other Jus-
tices, advances two theories—that the expert’s summary of the
Cellmark report was not offered for its truth, and that the report
is not the kind of statement triggering the Confrontation Clause’s
protection. In the pages that follow, I call Justice Alito’s
opinion “the plurality,” because that is the conventional term for
it. But in all except its disposition, his opinion is a dissent:
Five Justices specifically reject every aspect of its reasoning and
every paragraph of its explication. See ante, at 1 (Thomas, J.,
concurring in judgment) (“I share the dissent’s view of the
plurality’s flawed analysis”). Justice Thomas, for his part,
contends that the Cellmark report is nontestimonial on a different
rationale. But no other Justice joins his opinion or subscribes to
the test he offers.

															That creates five votes to approve the admission
of the Cellmark report, but not a single good explanation. The
plurality’s first rationale endorses a prosecutorial dodge; its
second relies on distinguishing indistinguishable forensic reports.
Justice Thomas’s concurrence, though positing an altogether
different approach, suffers in the end from similar flaws. I would
choose another path—to adhere to the simple rule established in our
decisions, for the good reasons we have previously given. Because
defendants like Williams have a constitutional right to confront
the witnesses against them, I respectfully dissent from the Court’s
fractured decision.

															I

															Our modern Confrontation Clause doctrine began
with Crawford v. Washington, 541 U.S.
36 (2004) . About a quarter century earlier, we had interpreted
the Clause to allow the admission of any out-of-court statement
falling within a “firmly rooted hearsay exception” or carrying
“particularized guarantees of trustworthiness.” Ohio v. Roberts, 448 U.S.
56 , 66 (1980) . But in Crawford, we concluded that our old
approach was misguided. Drawing on historical research about the
Clause’s purposes, we held that the prosecution may not admit
“testimonial statements of a witness who [does] not appear at trial
unless he [is] unavailable to testify, and the defendant
. . . had a prior opportunity for cross-examination.” 541
U. S., at 53–54. That holding has two aspects. First, the
Confrontation Clause applies only to out-of-court statements that
are “testimonial.” Second, where the Clause applies, it guarantees
to a defendant just what its name suggests—the opportunity to
cross-examine the person who made the statement. See id., at
59.

															A few years later, we made clear that Crawford’s
rule reaches forensic reports. In Melendez-Diaz v. Massachusetts, 557 U.S.
305 (2009) , the Commonwealth introduced a laboratory’s
“ ‘certificates of analysis’ ” stating that a substance
seized from the defendant was cocaine. Id., at 308. We held that
the certificates fell within the Clause’s “ ‘core class of
testimonial statements’ ” because they had a clear
“evidentiary purpose”: They were “ ‘made under circumstances
which would lead an objective witness reasonably to believe that
[they] would be available for use at a later trial.’ ” Id., at
310–311 (quoting Crawford, 541 U. S., at 51–52). Accordingly,
we ruled, the defendant had a right to cross-examine the analysts
who had authored them. In reaching that conclusion, we rejected the
Commonwealth’s argument that the Confrontation Clause should not
apply because the statements resulted from “ ‘neutral
scientific testing,’ ” and so were presumptively reliable. 557
U. S., at 318. The Clause, we noted, commands that
“ ‘reliability be assessed in a particular
manner’ ”—through “ ‘testing in the crucible of
cross-examination.’ ” Id., at 317 (quoting Crawford, 541
U. S., at 61). Further, we doubted that the testing summarized
in the certificates was “as neutral or as reliable” as the
Commonwealth suggested. Citing chapter and verse from various
studies, we concluded that “[f]orensic evidence is not uniquely
immune from the risk of manipulation” and mistake. 557 U. S.,
at 318; see id., at 319.

															And just two years later (and just one year
ago), we reiterated Melendez-Diaz’s analysis when faced with a
State’s attempt to evade it. In Bullcoming v. New Mexico, 564
U. S. ___ (2011), a forensic report showed the defendant’s
blood-alcohol concentration to exceed the legal limit for drivers.
The State tried to introduce that finding through the testimony of
a person who worked at the laboratory but had not performed or
observed the blood test or certified its results. We held that
Melendez-Diaz foreclosed that tactic. The report, we stated,
resembled the certificates in Melendez-Diaz in “all material
respects,” 564 U. S., at ___ (slip op., at 15): Both were
signed documents providing the results of forensic testing designed
to “ ‘prov[e] some fact’ in a criminal proceeding,” id., at
___ (slip op., at 14) (quoting Melendez-Diaz, 557 U. S., at
310). And the State’s resort to a “surrogate” witness, in place of
the analyst who produced the report, did not satisfy the
Confrontation Clause. Bullcoming, 564 U. S., at ___ (slip op.,
at 12). Only the presence of “that particular scientist,” we
reasoned, would enable Bullcoming’s counsel to ask “questions
designed to reveal whether incompetence . . . or
dishonesty” had tainted the results. Id., at ___, ___ (slip op., at
2, 12). Repeating the refrain of Melendez-Diaz, we held that “[t]he
accused’s right is to be confronted with” the actual analyst,
unless he is unavailable and the accused “had an opportunity,
pretrial, to cross-examine” him. Bullcoming, 564 U. S., at ___
(slip op., at 2).

															This case is of a piece. The report at issue
here shows a DNA profile produced by an analyst at Cellmark’s
laboratory, allegedly from a vaginal swab taken from a young woman,
L. J., after she was raped. That report is identical to the
one in Bullcoming (and Melendez-Diaz) in “all material respects.”
564 U. S., at ___ (slip op., at 15). Once again, the report
was made to establish “ ‘some fact’ in a criminal
proceeding”—here, the identity of L. J.’s attacker. Id., at
___ (slip op., at 14) (quoting Melendez-Diaz, 557 U. S., at
310); see infra, at 20. And once again, it details the results of
forensic testing on evidence gathered by the police. Viewed
side-by-side with the Bullcoming report, the Cellmark analysis has
a comparable title; similarly describes the relevant samples, test
methodology, and results; and likewise includes the signatures of
laboratory officials. Compare Cellmark Diagnostics Report of
Laboratory Examination (Feb. 15, 2001), Lodging of Petitioner with
App. in Bullcoming v. New Mexico, O. T. 2010, No. 09–10876,
pp. 62–65. So under this Court’s prior analysis, the substance of
the report could come into evidence only if Williams had a chance
to cross-examine the responsible analyst.

															But that is not what happened. Instead, the
prosecutor used Sandra Lambatos—a state-employed scientist who had
not participated in the testing—as the conduit for this piece of
evidence. Lambatos came to the stand after two other state analysts
testified about forensic tests they had performed. One recounted
how she had developed a DNA profile of Sandy Williams from a blood
sample drawn after his arrest. And another told how he had
confirmed the presence of (unidentified) semen on the vaginal swabs
taken from L. J. All this was by the book: Williams had an
opportunity to cross-examine both witnesses about the tests they
had run. But of course, the State still needed to supply the
missing link—it had to show that DNA found in the semen on
L. J.’s vaginal swabs matched Williams’s DNA. To fill that
gap, the prosecutor could have called the analyst from Cellmark to
testify about the DNA profile she had produced from the swabs. But
instead, the State called Lambatos as an expert witness and had her
testify that the semen on those swabs contained Sandy Williams’s
DNA:

															“Q Was there a computer match generated of the
male DNA profile found in semen from the vaginal swabs of
[L. J.] to a male DNA profile that had been identified as
having originated from Sandy Williams?

															“A Yes, there was.

															“Q Did you compare the semen . . .
from the vaginal swabs of [L. J.] to the male DNA profile
. . . from the blood of Sandy Williams?

															“A Yes, I did.

															.     .     .     .     .

															“Q [I]s the semen identified in the vaginal
swabs of [L. J.] consistent with having originated from Sandy
Williams?

															“A Yes.” App. 56–57.

															And so it was Lambatos, rather than any Cellmark
employee, who informed the trier of fact that the testing of
L. J.’s vaginal swabs had produced a male DNA profile
implicating Williams.

															Have we not already decided this case?
Lambatos’s testimony is functionally identical to the “surrogate
testimony” that New Mexico proffered in Bullcoming, which did
nothing to cure the problem identified in Melendez-Diaz (which, for
its part, straightforwardly applied our decision in Crawford). Like
the surrogate witness in Bullcoming, Lambatos “could not convey
what [the actual analyst] knew or observed about the events
. . . , i.e., the particular test and testing process he
employed.” Bullcoming, 564 U. S., at ___ (slip op., at 12).
“Nor could such surrogate testimony expose any lapses or lies” on
the testing analyst’s part. Ibid. Like the lawyers in Melendez-Diaz
and Bullcoming, Williams’s attorney could not ask questions about
that analyst’s “proficiency, the care he took in performing his
work, and his veracity.” 564 U. S., at ___, n. 7 (slip
op., at 12, n. 7). He could not probe whether the analyst had
tested the wrong vial, inverted the labels on the samples,
committed some more technical error, or simply made up the results.
See App. to Brief for Public Defender Service for the District of
Columbia et al. as Amici Curiae 5a, 11a (describing mistakes
and fraud at Cellmark’s laboratory). Indeed, Williams’s lawyer was
even more hamstrung than Bullcoming’s. At least the surrogate
witness in Bullcoming worked at the relevant laboratory and was
familiar with its procedures. That is not true of Lambatos: She had
no knowledge at all of Cellmark’s operations. Indeed, for all the
record discloses, she may never have set foot in Cellmark’s
laboratory.

															Under our case law, that is sufficient to
resolve this case. “[W]hen the State elected to introduce” the
substance of Cellmark’s report into evidence, the analyst who
generated that report “became a witness” whom Williams “had the
right to confront.” Bullcoming, 564 U. S., at ___ (slip op.,
at 13). As we stated just last year, “Our precedent[s] cannot
sensibly be read any other way.” Ibid.

															II

															The plurality’s primary argument to the
contrary tries to exploit a limit to the Confrontation Clause
recognized in Crawford. “The Clause,” we cautioned there, “does not
bar the use of testimonial statements for purposes other than
establishing the truth of the matter asserted.” 541 U. S., at
59–60, n. 9 (citing Tennessee v. Street, 471 U.S.
409 , 414 (1985) ). The Illinois Supreme Court relied on that
statement in concluding that Lambatos’s testimony was permissible.
On that court’s view, “Lambatos disclosed the underlying facts from
Cellmark’s report” not for their truth, but “for the limited
purpose of explaining the basis for her [expert] opinion,” so that
the factfinder could assess that opinion’s value. 238 Ill. 2d 125,
150, 939 N.E.2d 268, 282 (2010). The plurality wraps itself in that
holding, similarly asserting that Lambatos’s recitation of
Cellmark’s findings, when viewed through the prism of state
evidence law, was not introduced to establish “the truth of any
. . . matter concerning [the] Cellmark” report. Ante, at
16; see ante, at 2, 24–25. But five Justices agree, in two opinions
reciting the same reasons, that this argument has no merit:
Lambatos’s statements about Cellmark’s report went to its truth,
and the State could not rely on her status as an expert to
circumvent the Confrontation Clause’s requirements. See ante, at
2–8 (opinion of Thomas, J.).

															To see why, start with the kind of case
Crawford had in mind. In acknowledging the not-for-the-truth
carveout from the Clause, the Court cited Tennessee v. Street as
exemplary. See Crawford, 541 U. S., at 59–60, n. 9.
There, Street claimed that his stationhouse confession of murder
was a sham: A police officer, he charged, had read aloud his
alleged accomplice’s confession and forced him to repeat it. To
help rebut that defense, the State introduced the other confession
into the record, so the jury could see how it differed from
Street’s. This Court rejected Street’s Confrontation Clause claim
because the State had offered the out-of-court statement not to
prove “the truth of [the accomplice’s] assertions” about the
murder, but only to disprove Street’s claim of how the police
elicited his confession. Street, 471 U. S., at 413. Otherwise
said, the truth of the admitted statement was utterly immaterial;
the only thing that mattered was that the statement (whether true
or false) varied from Street’s.

															The situation could not be more different when a
witness, expert or otherwise, repeats an out-of-court statement as
the basis for a conclusion, because the statement’s utility is then
dependent on its truth. If the statement is true, then the
conclusion based on it is probably true; if not, not. So to
determine the validity of the witness’s conclusion, the factfinder
must assess the truth of the out-of-court statement on which it
relies. That is why the principal modern treatise on evidence
variously calls the idea that such “basis evidence” comes in not
for its truth, but only to help the factfinder evaluate an expert’s
opin- ion “very weak,” “factually implausible,” “nonsense,” and
“sheer fiction.” D. Kaye, D. Bernstein, & J. Mnookin, The New
Wigmore: Expert Evidence §4.10.1, pp. 196–197 (2d ed. 2011); id.,
§4.11.6, at 24 (Supp. 2012). “One can sympathize,” notes that
treatise, “with a court’s desire to permit the disclosure of basis
evidence that is quite probably reliable, such as a routine
analysis of a drug, but to pretend that it is not being introduced
for the truth of its contents strains credibility.” Id., §4.10.1,
at 198 (2d ed. 2011); see also, e.g., People v. Goldstein, 6 N.Y.3d
119, 128, 843 N.E.2d 727, 732–733 (2005) (“The distinction between
a statement offered for its truth and a statement offered to shed
light on an expert’s opinion is not meaningful”). Unlike in Street,
admission of the out-of-court statement in this context has no
purpose separate from its truth; the factfinder can do nothing with
it except assess its truth and so the credibility of the conclusion
it serves to buttress. [ 1 ]

															Consider a prosaic example not involving
scientific experts. An eyewitness tells a police officer
investigating an assault that the perpetrator had an unusual,
star-shaped birthmark over his left eye. The officer arrests a
person bearing that birthmark (let’s call him Starr) for committing
the offense. And at trial, the officer takes the stand and recounts
just what the eyewitness told him. Presumably the plurality would
agree that such testimony violates the Confrontation Clause unless
the eyewitness is unavailable and the defendant had a prior
opportunity to cross-examine him. Now ask whether anything changes
if the officer couches his testimony in the following way: “I
concluded that Starr was the assailant because a reliable
eyewitness told me that the assailant had a star-shaped birthmark
and, look, Starr has one just like that.” Surely that framing would
make no constitutional difference, even though the eyewitness’s
statement now explains the basis for the officer’s conclusion. It
remains the case that the prosecution is attempting to introduce a
testimonial statement that has no relevance to the proceedings
apart from its truth—and that the defendant cannot cross-examine
the person who made it. Allowing the admission of this evidence
would end-run the Confrontation Clause, and make a parody of its
strictures.

															And that example, when dressed in scientific
clothing, is no different from this case. The Cellmark report
identified the rapist as having a particular DNA profile (think of
it as the quintessential birthmark). The Confrontation Clause
prevented the State from introducing that report into evidence
except by calling to the stand the person who prepared it. See
Melendez-Diaz, 557 U. S., at 310–311; Bullcoming, 564
U. S., at ___ (slip op., at 2). So the State tried another
route—introducing the substance of the report as part and parcel of
an expert witness’s conclusion. In effect, Lambatos testified (like
the police officer above): “I concluded that Williams was the
rapist because Cellmark, an accredited and trustworthy laboratory,
says that the rapist has a particular DNA profile and, look,
Williams has an identical one.” And here too, that form of
testimony should change nothing. The use of the Cellmark statement
remained bound up with its truth, and the statement came into
evidence without any opportunity for Williams to cross-examine the
person who made it. So if the plurality were right, the State would
have a ready method to bypass the Constitution (as much as in my
hypothetical case); a wink and a nod, and the Confrontation Clause
would not pose a bar to forensic evidence.

															The plurality tries to make plausible its
not-for-the-truth rationale by rewriting Lambatos’s testimony about
the Cellmark report. According to the plurality, Lambatos merely
“assumed” that Cellmark’s DNA profile came from L. J.’s
vaginal swabs, accepting for the sake of argument the prosecutor’s
premise. Ante, at 18. But that is incorrect. Nothing in Lambatos’s
testimony indicates that she was making an assumption or
considering a hypothesis. To the contrary, Lambatos affirmed,
without qualification, that the Cellmark report showed a “male DNA
profile found in semen from the vaginal swabs of [L. J.].”
App. 56. Had she done otherwise, this case would be different.
There was nothing wrong with Lambatos’s testifying that two DNA
profiles—the one shown in the Cellmark report and the one derived
from Williams’s blood—matched each other; that was a
straightforward application of Lambatos’s expertise. Similarly,
Lambatos could have added that if the Cellmark report resulted from
scientifically sound testing of L. J.’s vaginal swab, then it
would link Williams to the assault. What Lambatos could not do was
what she did: indicate that the Cellmark report was produced in
this way by saying that L. J.’s vaginal swab contained DNA
matching Williams’s. [ 2 ] By
testifying in that manner, Lambatos became just like the surrogate
witness in Bullcoming—a person knowing nothing about “the
particular test and testing process,” but vouching for them
regardless. 564 U. S., at ___ (slip op., at 12). We have held
that the Confrontation Clause requires something more.

															The plurality also argues that Lambatos’s
characterization of the Cellmark report did not violate the
Confrontation Clause because the case “involve[d] a bench trial.”
Ante, at 19 (emphasis deleted). I welcome the plurality’s
concession that the Clause might forbid presenting Lambatos’s
statement to a jury, see ante, at 18–19; it indicates that the
plurality realizes that her testimony went beyond an “assumption.”
But the presence of a judge does not transform the constitutional
question. In applying the Confrontation Clause, we have never
before considered relevant the decisionmaker’s identity. See, e.g.,
Davis v. Washington, 547 U.S.
813 (2006) . And this case would be a poor place to begin.
Lambatos’s description of the Cellmark report was offered for its
truth because that is all such “basis evidence” can be offered for;
as described earlier, the only way the factfinder could consider
whether that statement supported her opinion (that the DNA on
L. J.’s swabs came from Williams) was by assessing the
statement’s truth. See supra, at 9–12. That is so, as a simple
matter of logic, whether the factfinder is a judge or a jury. And
thus, in either case, admission of the statement, without the
opportunity to cross-examine, violates the Confrontation Clause.
See ante, at 3–4, n. 1 (opinion of Thomas, J.).

															In saying that much, I do not doubt that a judge
typi- cally will do better than a jury in excluding such
inadmissible evidence from his decisionmaking process. Perhaps the
judge did so here; perhaps, as the plurality thinks, he un-
derstood that he could not consider Lambatos’s repre- sentation
about the Cellmark report, and found that other, “circumstantial
evidence” established “the source of the sample that Cellmark
tested” and “the reliability of the Cellmark profile.” See ante, at
22–23. Some indications are to the contrary: In delivering his
verdict, the judge never referred to the circumstantial evidence
the plurality marshals, but instead focused only on Lambatos’s
testimony. See 4 Record JJJ151 (calling Lambatos “the best DNA
witness I have ever heard” and referring to Williams as “the guy
whose DNA, according to the evidence from the experts, is in the
semen recovered from the victim’s vagina”). But I take the
plurality’s point that when read “[i]n context” the judge’s
statements might be “best understood” as meaning something other
than what they appear to say. See ante, at 20, n. 6. Still,
that point suggests only that the admission of Lambatos’s statement
was harmless—that the judge managed to put it out of mind. After
all, whether a factfinder is confused by an error is a separate
question from whether an error has occurred. So the plurality’s
argument does not answer the only question this case presents:
whether a constitutional violation happened when Lambatos recited
the Cellmark report’s findings. [ 3 ]

															At bottom, the plurality’s not-for-the-truth
rationale is a simple abdication to state-law labels. Although the
utility of the Cellmark statement that Lambatos repeated logi-
cally depended on its truth, the plurality thinks this case decided
by an Illinois rule holding that the facts underlying an expert’s
opinion are not admitted for that purpose. See ante, at 14–18;
People v. Pasch, 152 Ill. 2d 133 , 175–177, 604 N.E.2d 294 , 311 (1992). But we do not typically allow state
law to define federal constitutional requirements. And needless to
say (or perhaps not), the Confrontation Clause is a constitutional
rule like any other. As Justice Thomas observes, even before
Crawford, we did not allow the Clause’s scope to be “dictated by
state or federal evidentiary rules.” See ante, at 2. Indeed, in
Street, we independently reviewed whether an out-of-court statement
was introduced for its truth—the very question at issue in this
case. See 471 U. S., at 413–416. And in Crawford, we still
more firmly disconnected the Confrontation Clause inquiry from
state evidence law, by overruling an approach that looked in part
to whether an out- of-court statement fell within a “ ‘firmly
rooted hearsay exception.’ ” 541 U. S., at 60 (quoting
Roberts, 448 U. S., at 66). That decision made clear that the
Confrontation Clause’s protections are not coterminous with rules
of evidence. So the plurality’s state-law-first approach would be
an about-face.

															Still worse, that approach would allow
prosecutors to do through subterfuge and indirection what we
previously have held the Confrontation Clause prohibits. Imagine
for a moment a poorly trained, incompetent, or dishonest laboratory
analyst. (The analyst in Bullcoming, placed on unpaid leave for
unknown reasons, might qualify.) Under our precedents, the
prosecutor cannot avoid exposing that analyst to cross-examination
simply by introducing his report. See Melendez-Diaz, 557
U. S., at 311. Nor can the prosecutor escape that fate by
offering the results through the testimony of another analyst from
the laboratory. See Bullcoming, 564 U. S., at ___ (slip op.,
at 2). But under the plurality’s approach, the prosecutor could
choose the analyst-witness of his dreams (as the judge here said,
“the best DNA witness I have ever heard”), offer her as an expert
(she knows nothing about the test, but boasts impressive degrees),
and have her provide testimony identical to the best the actual
tester might have given (“the DNA extracted from the vaginal swabs
matched Sandy Williams’s”)—all so long as a state evidence rule
says that the purpose of the testimony is to enable the factfinder
to assess the expert opinion’s basis. (And this tactic would not be
confined to cases involving scientific evidence. As Justice Thomas
points out, the prosecutor could similarly substitute experts for
all kinds of people making out-of-court statements. See ante, at
7.) The plurality thus would countenance the Constitution’s
circumvention. If the Confrontation Clause prevents the State from
getting its evidence in through the front door, then the State
could sneak it in through the back. What a neat trick—but really,
what a way to run a criminal justice system. No wonder five
Justices reject it.

															III

															The plurality also argues, as a “second,
independent basis” for its decision, that the Cellmark report falls
outside the Confrontation Clause’s ambit because it is
nontestimonial. Ante, at 3. The plurality tries out a number of
supporting theories, but all in vain: Each one either conflicts
with this Court’s precedents or misconstrues this case’s facts.
Justice Thomas rejects the plurality’s views for similar reasons as
I do, thus bringing to five the number of Justices who repudiate
the plurality’s understanding of what statements count as
testimonial. See ante, at 1, 12–15. Justice Thomas, however, offers
a rationale of his own for deciding that the Cellmark report is
nontestimonial. I think his essay works no better. When all is said
and done, the Cellmark report is a testimonial statement.

															A

															According to the plurality, we should declare
the Cellmark report nontestimonial because “the use at trial of a
DNA report prepared by a modern, accredited laboratory ‘bears
little if any resemblance to the historical practices that the
Confrontation Clause aimed to eliminate.’ ” Ante, at 33
(quoting Michigan v. Bryant, 562 U. S. ___, ___ (2011)
(Thomas, J., concurring in judgment) (slip op., at 2)). But we just
last year treated as testimonial a forensic report prepared by a
“modern, accredited laboratory”; indeed, we declared that the
report at issue “fell within the core class of testimonial
statements” implicating the Confrontation Clause. Bullcoming, 564
U. S., at ___ (slip op., at 16) (internal quotation marks
omitted); see Brief for New Mexico Department of Health, Scientific
Laboratory Division as Amicus Curiae in Bullcoming, O. T. 2010, No.
09–10786, p. 1 (discussing accreditation). And although the
plurality is close, it is not quite ready (or able) to dispense
with that decision. See ante, at 29, n. 13 (“Experience might
yet show that the holdings in [Bullcoming and other post-Crawford]
cases should be reconsidered”). So the plurality must explain: What
could support a distinction between the laboratory analysis there
and the DNA test in this case? [ 4 ]

															As its first stab, the plurality states that the
Cellmark report was “not prepared for the primary purpose of
accusing a targeted individual.” Ante, at 31. Where that test comes
from is anyone’s guess. Justice Thomas rightly shows that it
derives neither from the text nor from the history of the
Confrontation Clause. See ante, at 14–15 (opinion concurring in
judgment). And it has no basis in our precedents. We have
previously asked whether a statement was made for the primary
purpose of establishing “past events potentially relevant to later
criminal prosecution”—in other words, for the purpose of providing
evidence. Davis, 547 U. S., at 822; see also Bullcoming, 564
U. S., at ___ (slip op., at 14); Bryant, 562 U. S., at
___, ___ (slip op., at 14, 29); Melendez-Diaz, 557 U. S., at
310–311; Crawford, 541 U. S., at 51–52. None of our cases has
ever suggested that, in addition, the statement must be meant to
accuse a previously identified individual; indeed, in
Melendez-Diaz, we rejected a related argument that laboratory
“analysts are not subject to confrontation because they are not
‘accusatory’ witnesses.” 557 U. S., at 313.

															Nor does the plurality give any good reason for
adopting an “accusation” test. The plurality apparently agrees with
Justice Breyer that prior to a suspect’s identification, it will be
“unlikely that a particular researcher has a defendant-related
motive to behave dishonestly.” Ante, at 12 (Breyer, J.,
concurring); see ante, at 31–32 (plurality opinion). But surely the
typical problem with laboratory analyses—and the typical focus of
cross-examination—has to do with careless or incompetent work,
rather than with personal vendettas. And as to that predominant
concern, it makes not a whit of difference whether, at the time of
the laboratory test, the police already have a suspect. [ 5 ]

															The plurality next attempts to invoke our
precedents holding statements nontestimonial when made “to respond
to an ‘ongoing emergency,’ ” rather than to create evidence
for trial, Bryant, 562 U. S., at ___ (slip op., at 11); here,
the plurality insists, the Cellmark report’s purpose was “to catch
a dangerous rapist who was still at large.” Ante, at 31. But that
is to stretch both our “ongoing emergency” test and the facts of
this case beyond all recognition. We have previously invoked that
test to allow statements by a woman who was being assaulted and a
man who had just been shot. In doing so, we stressed the “informal
[and] harried” nature of the statements, Bryant, 562 U. S., at
___ (slip op., at 31)—that they were made as, or “minutes” after,
id., at ___ (slip op., at 28), the events they described “actually
happen[ed],” Davis, 547 U. S., at 827 (emphasis deleted), by
“frantic” victims of criminal attacks, ibid., to officers trying to
figure out “what had . . . occurred” and what threats
remained, Bryant, 562 U. S., at ___ (slip op., at 30)
(internal quotation marks omitted). On their face, the decisions
have nothing to say about laboratory analysts conducting routine
tests far away from a crime scene. And this case presents a
peculiarly inapt set of facts for extending those precedents.
Lambatos testified at trial that “all reports in this case were
prepared for this criminal investigation . . . [a]nd for
the purpose of the eventual litigation,” App. 82—in other words,
for the purpose of producing evidence, not enabling emergency
responders. And that testimony fits the relevant timeline. The
police did not send the swabs to Cellmark until November 2008—nine
months after L. J.’s rape—and did not receive the results for
another four months. See id., at 30–34, 51–52, 54. That is hardly
the typical emergency response.

															Finally, the plurality offers a host of reasons
for why reports like this one are reliable: “[T]here [i]s no
prospect of fabrication,” ante, at 31 (internal quotation marks
omitted); multiple technicians may “work on each DNA profile,”
ante, at 32; and “defects in a DNA profile may often be detected
from the profile itself,” ibid. See also ante, at 10–14 (opinion of
Breyer, J.). But once again: Been there, done that. In
Melendez-Diaz, this Court rejected identical arguments, noting
extensive documentation of “[s]erious deficiencies . . .
in the forensic evidence used in criminal trials.” 557 U. S.,
at 319; see supra, at 4–5; see also Bullcoming, 564 U. S., at
___, n. 1 (slip op., at 4, n. 1) (citing similar errors in
laboratory analysis); Brief for Public Defender Service for the
District of Columbia et al. as Amici Curiae 13 (discussing
“[s]ystemic problems,” such as sample contamination, sample
switching, mislabeling, and fraud, at “ ‘flagship’ DNA labs”).
Scientific testing is “technical,” to be sure, ante, at 1 (opinion
of Breyer, J.); but it is only as reliable as the people who
perform it. That is why a defendant may wish to ask the analyst a
variety of questions: How much experience do you have? Have you
ever made mistakes in the past? Did you test the right sample? Use
the right procedures? Contaminate the sample in any way? Indeed, as
scientific evidence plays a larger and larger role in criminal
prosecutions, those inquiries will often be the most important in
the case. [ 6 ]

															And Melendez-Diaz made yet a more fundamental
point in response to claims of the über alles reliability of
scientific evidence: It is not up to us to decide, ex ante, what
evidence is trustworthy and what is not. See 557 U. S., at
317–318; see also Bullcoming, 564 U. S., at ___ (slip op., at
11). That is because the Confrontation Clause prescribes its own
“procedure for determining the reliability of testimony in criminal
trials.” Crawford, 541 U. S., at 67. That procedure is
cross-examination. And “[d]ispensing with [it] because testimony is
obviously reliable is akin to dispensing with jury trial because a
defendant is obviously guilty.” Id., at 62.

															So the plurality’s second basis for denying
Williams’s right of confrontation also fails. The plurality can
find no reason consistent with our precedents for treating the
Cellmark report as nontestimonial. That is because the report is,
in every conceivable respect, a statement meant to serve as
evidence in a potential criminal trial. And that simple fact should
be sufficient to resolve the question.

															B

															Justice Thomas’s unique method of defining
testimonial statements fares no better. On his view, the
Confrontation Clause “regulates only the use of statements bearing
‘indicia of solemnity.’ ” Ante, at 8 (quoting Davis, 547
U. S., at 836–837). And Cellmark’s report, he concludes, does
not qualify because it is “neither a sworn nor a certified
declaration of fact.” Ante, at 9. But Justice Thomas’s approach
grants constitutional significance to minutia, in a way that can
only undermine the Confrontation Clause’s protections.

															To see the point, start with precedent, because
the Court rejected this same kind of argument, as applied to this
same kind of document, at around this same time just last year. In
Bullcoming, the State asserted that the forensic report at issue
was nontestimonial because—unlike the report in Melendez-Diaz—it
was not sworn before a notary public. We responded that applying
the Confrontation Clause only to a sworn forensic report “would
make the right to confrontation easily erasable”—next time, the
laboratory could file the selfsame report without the oath. 564
U. S., at ___ (slip op., at 15). We then held, as noted
earlier, that “[i]n all material respects,” the forensic report in
Bullcoming matched the one in Melendez-Diaz. 564 U. S., at ___
(slip op., at 15); see supra, at 5. First, a law enforcement
officer provided evidence to a state laboratory assisting in police
investigations. See 564 U. S., at ___ (slip op., at 15).
Second, the analyst tested the evidence and “prepared a certificate
concerning the result[s].” Ibid. Third, the certificate was
“formalized in a signed document . . . headed a
‘report.’ ” Ibid. (some internal quotation marks omitted).
That was enough.

															Now compare that checklist of “material”
features to the report in this case. The only differences are that
Cellmark is a private laboratory under contract with the State
(which no one thinks relevant), and that the report is not labeled
a “certificate.” That amounts to (maybe) a nickel’s worth of
difference: The similarities in form, function, and purpose dwarf
the distinctions. See supra, at 5–6. Each report is an official and
signed record of laboratory test results, meant to establish a
certain set of facts in legal proceedings. Neither looks any more
“formal” than the other; neither is any more formal than the other.
See ibid. The variances are no more (probably less) than would be
found if you compared different law schools’ transcripts or
different companies’ cash flow statements or different States’
birth certificates. The difference in labeling—a “certificate” in
one case, a “report of laboratory examination” in the other—is not
of constitutional dimension.

															Indeed, Justice Thomas’s approach, if accepted,
would turn the Confrontation Clause into a constitutional
geegaw—nice for show, but of little value. The prosecution could
avoid its demands by using the right kind of forms with the right
kind of language. (It would not take long to devise the magic words
and rules—principally, never call anything a “certificate.”) [ 7 ] And still worse: The new
conventions, precisely by making out-of-court statements less
“solem[n],” ante, at 1, would also make them less reliable—and so
turn the Confrontation Clause upside down. See Crawford, 541
U. S., at 52–53, n. 3 (“We find it implausible that a
provision which concededly condemned trial by sworn ex parte
affidavit thought trial by unsworn ex parte affidavit
perfectly OK”). It is not surprising that no other Member of the
Court has adopted this position. To do so, as Justice Thomas
rightly says of the plurality’s decision, would be to “diminis[h]
the Confrontation Clause’s protection” in “the very cases in which
the accused should ‘enjoy the right . . . to be
confronted with the witnesses against him.’ ” Ante, at 16.

															IV

															Before today’s decision, a prosecutor wishing to
admit the results of forensic testing had to produce the technician
responsible for the analysis. That was the result of not one, but
two decisions this Court issued in the last three years. But that
clear rule is clear no longer. The five Justices who control the
outcome of today’s case agree on very little. Among them, though,
they can boast of two accomplishments. First, they have approved
the introduction of testimony at Williams’s trial that the
Confrontation Clause, rightly understood, clearly prohibits.
Second, they have left significant confusion in their wake. What
comes out of four Justices’ desire to limit Melendez-Diaz and
Bullcoming in whatever way possible, combined with one Justice’s
one-justice view of those holdings, is—to be frank—who knows what.
Those decisions apparently no longer mean all that they say. Yet no
one can tell in what way or to what extent they are altered because
no proposed limitation commands the support of a majority.

															The better course in this case would have been
simply to follow Melendez-Diaz and Bullcoming. Precedent-based
decisionmaking provides guidance to lower court judges and
predictability to litigating parties. Today’s plurality and
concurring opinions, and the uncertainty they sow, bring into
relief that judicial method’s virtues. I would decide this case
consistently with, and for the reasons stated by, Melendez-Diaz and
Bullcoming. And until a majority of this Court reverses or confines
those decisions, I would understand them as continuing to govern,
in every particular, the admission of forensic evidence.

															I respectfully dissent. Notes 1 In responding to this
reasoning, the plurality confirms it. According to the plurality,
basis evidence supports the “credibility of the expert’s opinion”
by showing that he has relied on, and drawn logical inferences
from, sound “factual premises.” Ante, at 24. Quite right. And that
process involves assessing such premises’ truth: If they are, as
the majority puts it, “unsupported by other evidence in the record”
or otherwise baseless, they will not “allay [a factfinder’s] fears”
about an “expert’s reasoning.” Ante, at 24–25. I could not have
said it any better. 2 The plurality suggests
that Lambatos’s testimony is merely a modern, streamlined way of
answering hypothetical questions and therefore raises no
constitutional issue, see ante, at 2, 13–15; similarly, the
plurality contends that the difference between what Lambatos said
and what I would allow involves only “slightly revis[ing]” her
testimony and so can be of no consequence, see ante, at 18,
n. 3. But the statement “if X is true, then Y follows” differs
materially—and constitutionally—from the statement “Y is true
because X is true (according to Z).” The former statement is merely
a logical proposition, whose validity the defendant can contest by
questioning the speaker. And then, assum-ing the prosecutor tries
to prove the statement’s premise through some other witness, the
defendant can rebut that effort through cross-examination. By
contrast, the latter statement as well contains a factual
allegation (that X is true), which the defendant can only
effectively challenge by confronting the person who made it (Z).
That is why recognizing the difference between these two forms of
testimony is not to insist on an archaism or a formality, but to
ensure, in line with the Constitution, that defendants have the
ability to confront their accusers. And if prosecutors can easily
conform their conduct to that constitutional directive, as the
plurality suggests, so much the better: I would not have thought it
a ground of complaint that the Confrontation Clause, properly
understood, manages to protect defendants without overly burdening
the State. 3 The plurality asserts
(without citation) that I am “reach[ing] the truly remarkable
conclusion that the wording of Lambatos’ testimony confused the
trial judge,” ante, at 19, and then spends three pages explaining
why that conclusion is wrong, see ante, at 19–21. But the plurality
is responding to an argument of its own imagining, because I reach
no such conclusion. As I just stated, the trial judge might well
have ignored Lambatos’s statement about the Cellmark report and
relied on other evidence to conclude that “the Cellmark profile was
derived from the sample taken from the victim,” ante, at 19. All I
am saying is that the admission of that statement violated the
Confrontation Clause even if the judge ultimately put it aside,
because it came into evidence for nothing other than its truth. See
supra, at 9–12. Similarly, the plurality claims (still without
citation) that I think the other evidence about the Cellmark report
insufficient, see ante, at 21. But once again, the plurality must
be reading someone else’s opinion. I express no view on sufficiency
of the evidence because it is irrelevant to the Confrontation
Clause issue we took this case to decide. It is the plurality that
wrongly links the two, spending another five pages trumpeting the
strength of the Cellmark report, see ante, at 22–24, 32–33. But the
plurality cannot properly decide whether a Confrontation Clause
violation occurred at Williams’s trial by determining that Williams
was guilty. The American criminal justice system works the opposite
way: determining guilt by holding trials in accord with
constitutional requirements. 4 Justice Breyer does not
attempt to distinguish our precedents, opting simply to adhere to
“the dissenting view set forth in Melendez-Diaz and Bullcoming.”
See ante, at 8 (concurring opinion). He principally worries that
under those cases, a State will have to call to the witness stand
“[s]ix to twelve or more technicians” who have worked on a report.
See ante, at 5; see also ante, at 3, 16–18. But none of our
cases—including this one—has presented the question of how many
analysts must testify about a given report. (That may suggest that
in most cases a lead analyst is readily identifiable.) The problem
in the cases—again, including this one—is that no analyst came
forward to testify. In the event that some future case presents the
multiple-technician issue, the Court can focus on “the broader
‘limits’ question” that troubles Justice Breyer, ante, at 7. But
the mere existence of that question is no reason to wrongly decide
the case before us—which, it bears repeating, involved the
testimony of not twelve or six or three or one, but zero Cellmark
analysts. 5 Neither can the plurality
gain any purchase from the idea that a DNA profile is not
“inherently inculpatory” because it “tends to exculpate all but one
of the more than 7 billion people in the world today.” Ante, at 3;
see ante, at 32. All evidence shares this feature: the more
inculpatory it is of a single person, the more exculpatory it is of
the rest of the world. The one is but the flipside of the other.
But no one has ever before suggested that this logical corollary
provides a reason to ignore the Constitution’s efforts to ensure
the reliability of evidence. 6 Both the plurality and
Justice Breyer warn that if we require analysts to testify, we will
encourage prosecutors to forgo DNA evidence in favor of less
reliable eyewitness testimony and so “increase the risk of
convicting the innocent.” Ante, at 13 (Breyer, J., concurring); see
ante, at 3–4 (plurality opinion). Neither opinion provides any
evidence, even by way of anecdote, for that view, and I doubt any
exists. DNA evidence is usually the prosecutor’s most powerful
weapon, and a prosecutor is unlikely to relinquish it just because
he must bring the right analyst to the stand. Consider what
Lambatos told the factfinder here: The DNA in L. J.’s vaginal
swabs matched Williams’s DNA and would match only “1 in 8.7
quadrillion black, 1 in 390 quadrillion white, or1 in 109
quadrillion Hispanic unrelated individuals.” App. 56–57. No
eyewitness testimony could replace that evidence. I note as well
that the Innocence Network—a group particularly knowledgeable about
the kinds of evidence that produce erroneous convictions—disagrees
with the plurality’s and Justice Breyer’s view. It argues here that
“[c]onfrontation of the analyst . . . is essential to permit proper
adversarial testing” and so to decrease the risk of convicting the
innocent. Brieffor the Innocence Network as Amicus Curiae 3,
7. 7 Justice Thomas asserts
there is no need to worry, because “the Confrontation Clause
reaches bad-faith attempts to evade the formalized process.” Ante,
at 10; see ante, at 9, n. 5. I hope he is right. But Justice
Thomas provides scant guidance on how to conduct this novel inquiry
into motive.