Convictions based solely on DNA evidence In February 2017 the Court of Appeal ruled in the case of that where the sole evidence against a defendant was his DNA profile on a moveable object found at the scene of a crime, this would be sufficient to raise a case to answer. This decision overruled the position previously set out by the Court of Appeal in a number of cases including the case of R v Bryon [2015] EWCA Crim 997. In the defendant was charged with the theft of cash at a supermarket. A mixed DNA profile was found on an item left at the scene and the major proportion of the DNA matched the DNA of the defendant with a likelihood ratio of one in a billion. In addition to that evidence, the defendant had a conviction for theft carried out in exactly the same way. In giving his judgment Jackson LJ stated is clear from the authorities that where a moveable “it item is left at the scene with mixed DNA profiles, one of which matches the defendant’s profile, that on its own is not sufficient to support a conviction”. The Court of Appeal also suggested that the same may be true even if there was a single DNA profile on the item. The conviction was upheld but only because the DNA evidence was supported by the defendant’s bad character. Then followed the case of R v FNC . The Court of Appeal began questioning previous authorities where convictions based solely on DNA found on movable objects left at the scene had been quashed (Grant ; Ogden ). The case of FNC did not deal with moveable objects, but with DNA directly deposited during the course of the commission of an offence (semen left on a pair of trousers during a sexual assault). The Court observed however that improvements in the analysis and techniques of analysis of DNA had improved markedly in the last decade and so DNA on an article left at the scene may be sufficient to raise a case to answer where the match was in the order of one in a billion. This was considered further in the case of Tskeri a woman was attacked in her car in
Convictions based solely on DNA evidence In February 2017 the Court of Appeal ruled in the case of that where the sole evidence against a defendant was his DNA profile on a moveable object found at the scene of a crime, this would be sufficient to raise a case to answer. This decision overruled the position previously set out by the Court of Appeal in a number of cases including the case of R v Bryon [2015] EWCA Crim 997. In the defendant was charged with the theft of cash at a supermarket. A mixed DNA profile was found on an item left at the scene and the major proportion of the DNA matched the DNA of the defendant with a likelihood ratio of one in a billion. In addition to that evidence, the defendant had a conviction for theft carried out in exactly the same way. In giving his judgment Jackson LJ stated “it is clear from the authorities that where a moveable item is left at the scene with mixed DNA profiles, one of which matches the defendant’s profile, that on its own is not sufficient to support a conviction”. The Court of Appeal also suggested that the same may be true even if there was a single DNA profile on the item. The conviction was upheld but only because the DNA evidence was supported by the defendant’s bad character. Then followed the case of R v FNC . The Court of Appeal began questioning previous authorities where convictions based solely on DNA found on movable objects left at the scene had been quashed (Grant ; Ogden ). The case of FNC did not deal with moveable objects, but with DNA directly deposited during the course of the commission of an offence (semen left on a pair of trousers during a sexual assault). The Court observed however that improvements in the analysis and techniques of analysis of DNA had improved markedly in the last decade and so DNA on an article left at the scene may be sufficient to raise a case to answer where the match was in the order of one in a billion. This was considered further in the case of Tskeri a woman was attacked in her car in
Article_re_DNA_evidence.docx