SOURCE: Republished with permission of Taylor and Francis Group LLC Books, adapted from Karen E. Stein and Thomas M. Brown, Principles of Toxicology, Third Edition, 2015; permission conveyed through Copyright Clearance Center, Inc. The Tsosie Case: The retrograde extrapolation issue allows the instructor to discuss a recurring issue in many areas of scientific evidence. Should courts ever establish a causation requirement that the parties very often will be unable to meet? The Montana Supreme Court addressed this issue in State v. McGowan, 139 P.3d 841 (Mont. 2006). The court held that the state need not present evidence to establish a person's alcohol concentration at the time he or she was driving under the state's DUI per se statute. It recognized, the impossible burden that requiring retrograde extrapolation evidence would place on the state. Retrograde extrapolation would require evidence that the state would rarely be able to acquire because of a defendant's constitutional right to remain silent. Specifically, the state would need to ascertain information wholly within the defendant's knowledge, such as when, and in what amounts, the defendant consumed alcohol before driving. Further, the rate of absorption of alcohol varies greatly among individuals, with studies indicating that a person reaches their peak blood alcohol level anywhere from 14 to 138 minutes after drinking. Additionally, the amount of food consumed by the defendant affects the rate of absorption. We therefore agree with other jurisdictions that have concluded that the legislature “could not have intended to place such impossible roadblocks in the way of the State in prosecuting [DUI per se] cases.” Asking the impossible of litigants is a recurring concern in toxic-tort litigation. For example, in many situations, there can be no epidemiological evidence and, therefore, creating a requirement that the plaintiff provide it is tantamount to a rule that the plaintiff loses. Setting aside specific statutory requirements, the answer to the issue in these cases turns on two questions. First, did the defendant have any opportunity to consume alcohol between the time of driving and the time of the test? Obviously, if the answer is yes, then a presumption that the defendant's BAC while driving was as high as or higher than that indicated by the test is unwarranted. Thus, it is important for the state to show that the defendant had no opportunity to consume alcohol after arrest.
SOURCE: Republished with permission of Taylor and Francis Group LLC Books, adapted from Karen E. Stein and Thomas M. Brown, Principles of Toxicology, Third Edition, 2015; permission conveyed through Copyright Clearance Center, Inc. The Tsosie Case: The retrograde extrapolation issue allows the instructor to discuss a recurring issue in many areas of scientific evidence. Should courts ever establish a causation requirement that the parties very often will be unable to meet? The Montana Supreme Court addressed this issue in State v. McGowan, 139 P.3d 841 (Mont. 2006). The court held that the state need not present evidence to establish a person's alcohol concentration at the time he or she was driving under the state's DUI per se statute. It recognized, the impossible burden that requiring retrograde extrapolation evidence would place on the state. Retrograde extrapolation would require evidence that the state would rarely be able to acquire because of a defendant's constitutional right to remain silent. Specifically, the state would need to ascertain information wholly within the defendant's knowledge, such as when, and in what amounts, the defendant consumed alcohol before driving. Further, the rate of absorption of alcohol varies greatly among individuals, with studies indicating that a person reaches their peak blood alcohol level anywhere from 14 to 138 minutes after drinking. Additionally, the amount of food consumed by the defendant affects the rate of absorption. We therefore agree with other jurisdictions that have concluded that the legislature “could not have intended to place such impossible roadblocks in the way of the State in prosecuting [DUI per se] cases.” Asking the impossible of litigants is a recurring concern in toxic-tort litigation. For example, in many situations, there can be no epidemiological evidence and, therefore, creating a requirement that the plaintiff provide it is tantamount to a rule that the plaintiff loses. Setting aside specific statutory requirements, the answer to the issue in these cases turns on two questions. First, did the defendant have any opportunity to consume alcohol between the time of driving and the time of the test? Obviously, if the answer is yes, then a presumption that the defendant's BAC while driving was as high as or higher than that indicated by the test is unwarranted. Thus, it is important for the state to show that the defendant had no opportunity to consume alcohol after arrest.