Controversies in DNA profiling
Prof Allan Jamieson
Developments in DNA technology have increased the specificity and sensitivity well beyond the original application which required a visible amount of body fluid (e.g. blood, semen, saliva).
Profiling smaller and smaller amounts of recovered cellular material produces new problems in the interpretation of profiles. There are various methods claimed to interpret the evidential significance of a mixed DNA profile, and the debate about which is best continues.
But, even as that scientific debate persists about the best way to interpret DNA mixtures, two developments have followed efforts to extract more evidence from ever-smaller amounts of DNA.
One of these is Low Copy Number (LCN) or Low Template DNA analysis which continues to be challenged in courts around the world. One complication of Low Template profiles is the occurrence of the voids previously disparaged by the Appeal Court of England & Wales (R v Bates[1]). Although the challenge in England & Wales was effectively extinguished in R v Reed & Reed [2] , challenges continue in courts internationally to the reliability of such profiles (e.g. [3],[4],[5],[6]).
The second development is the introduction of statistical methods to deal with these voids; so complex that they can only produce results using 'expert systems'. A number of software programmes have been developed that claim to perform these.
As the improving technology of profiling allowed smaller amounts of material to be profiled, so it became possible to obtain profiles from material invisible to the naked eye. Experts in some cases opine that one mechanism is more likely than another using their 'casework experience'.
[1] R v Bates [2006] EWCA Crim 1395
[2] R v Reed & Reed and Garmson [2009] EWCA Crim 2698
[3] US v McCluskey Cr. No. 10-2734 JCH (New Mexico)
[4] People v Espino (2009) NA076620
[5] People v Megnath (2010) NY Slip Op 20037 [27 Misc 3d 405]
[6] R v Wallace [2010] NZCA 46 (CA590/2007)
Professor Jamieson is the Director of The Forensic Institute, Glasgow and Visiting Professor of Forensic Science at Staffordshire University. He is an internationally recognised expert in criminal cases having provided evidence and advice in over 1000 cases including high profile cases such as the Omagh Bomb trial of Sean Hoey, the inquest into the death of Diana, Princess of Wales, and cases at the Court of Criminal Appeal including RvT, RvOtway, and R v Reed & Anor. He is Co-Editor in Chief of the 6-volume Wiley’s Encyclopaedia of Forensic Sciences. He is the founder of The Forensic Institute Research Network and FORREST.