BAYESIAN-ANALYSIS OF DNA PROFILING DATA IN FORENSIC IDENTIFICATION APPLICATIONS

The utilization of DNA evidence in cases of forensic identification ha s become widespread over the last few years. The strength of this evid ence against an individual standing trial is typically presented in co urt in the form of a likelihood ratio (LR) or its reciprocal (the prof ile match probability). The value of this LR will vary according to th e nature of the genetic relationship between the accused and other pos sible perpetrators of the crime in the population. This paper develops ideas and methods for analysing data and evaluating LRs when the evid ence is based on short tandem repeat profiles, with special emphasis p laced on a Bayesian approach. These are then applied in the context of a particular quadruplex profiling system used for routine case-work b y the UK Forensic Science Service.