The field of DNA identification is rapidly changing and becoming increasingly accurate as time goes on. Early DNA matching was painfully slow and relatively primitive. Now, computers can quickly determine with a remarkably high degree of accuracy whether or not two DNA samples came from the same person. One of the newest technologies, True Allele, is so accurate that the odds of error are 1 in 189 billion. It was this technology that resulted in a conviction in the 2009 Pennsylvania murder case Commonwealth v. Foley.
The purported accuracy of True Allele and other DNA testing technology is certainly convincing, especially to a jury. But new scientific methods should not be used as evidence in a court of law without first passing the Frye test, which is used to determine if a method has stood up to the rigor of general acceptance in the scientific community. In Foley, defendant Kevin Foley was found guilty of murder, primarily as a result of DNA that was collected and analyzed using True Allele. Foley’s attorneys appealed the conviction to the Pennsylvania Superior Court, arguing that the True Allele technology does not pass the Frye test. However, in a unanimous decision in 2012, the Court affirmed the verdict, ruling that the method does in fact pass the Frye test. Specifically, the Court found that the method has withstood the scrutiny of peer review from the scientific community, and that the technology is “not novel”, given that it has been used in multiple other agencies around the world.
Even though the True Allele method passed the Frye test, not all new technologies do (see our blog article on granulization, a cell phone tracing method). Until the technology in question has been deemed acceptable in court, the defense attorney should always challenge the admissibility of it under Frye.