The Admissibility of TrueAllele: A Computerized DNA Interpretation System

Table of ContentsI. Introduction 1034II. The Admissibility of Scientific Evidence 1037A. Scientific Admissibility Doctrines 10391. The Frye Standard: General Acceptance 10392. The Daubert Standard: A Five-Factor Balancing Test 10403. Post-Daubert's Practical Impact and Comparing the Standards 1043B. Early Admissibility of DNA Evidence 10441. Early Controversies About the Admissibility of DNA Evidence 10452. Post-Daubert Admissibility of DNA Evidence 1051III. Understanding DNA as Scientific Evidence 1053A. The Basic Principles of DNA 1053B. Genetic Identification: Methods of DNA Typing 1055C. Human Interpretation of DNA Profiles 1056D. Computer Interpretation of DNA Profiles: TrueAllele 1059IV. The Admissibility of TrueAllele 1061A. TrueAllele Precedent 10611. Regina v. Colin Duffy & Brian Shivers 10622. Commonwealth v. Foley 10653. Ohio v. Shaw 1068B. TrueAllele Admissibility Issues 1071V. TrueAllele and the Norms of Criminal Procedure: What is the Proper Admissibility Analysis? 1073I. IntroductionIn criminal cases, the stakes regarding DNA evidence run high. The admissibility of one piece of DNA evidence can alter the outcome of the case. Imagine that the prosecution charges Mr. Smith with murder. The police found what they believe is Mr. Smith's DNA on the victim at the scene of the crime. They send the sample to the Department of Forensic laboratory. Technicians at the laboratory use a certain method of DNA interpretation called "human interpretation." Based on this method, the lab reports an inconclusive result. The result may be inconclusive because the sample is too complex (contains too many contributors) or is degraded or contaminated. The result might be inconclusive because the DNA does not belong to Mr. Smith. Regardless, without conclusive DNA evidence tying Mr. Smith to the scene of the crime, the prosecution may be unable to meet its burden of proof that Mr. Smith committed the murder. Now imagine that the Department of Forensic laboratory recently implemented a new type of DNA interpretation technology. Instead of the traditional human interpretation technique, the lab uses new computerized DNA interpretation technology. Using the technology, the lab yields conclusive results. An expert for the prosecution testifies that Mr. Smith's DNA matches the sample DNA found on the victim, and a jury convicts Mr. Smith.In criminal cases, the prosecution carries the heavy burden of proof-beyond a reasonable doubt-for each and every element of a crime.1 In the past few decades, technological advances have aided the prosecution in carrying this burden. Specifically, the advent of DNA technology allows prosecutors to conclusively allege, in numerical terms, the likelihood that a particular defendant's DNA is present at a particular location. Admissibility of scientific evidence hinges on standards developed in the early 1900s.2 These standards continuously developed over subsequent decades.3 Like many areas of the law, the standards may struggle to keep up with evolving technology. Recently, innovative computer interpretation programs began replacing widely accepted human interpretation of DNA evidence. …