Forensics techniques found not to be as accurate as thought

Ars Technica : Because of problems with forensics practices raised in a 2009 report from the National Research Council, President Obama asked the President’s Council of Advisors on Science and Technology (PCAST) to investigate the validity of forensic evidence. Among the techniques examined were hair, DNA, fingerprint, firearm marking, footwear, and bite-mark analyses. According to the PCAST report , which has just been released, all those techniques have problems. The least reliable is bite-mark analysis because the technique cannot reliably establish the source of a bite or determine whether it was inflicted by a human. DNA analysis, although found to be scientifically sound, can be prone to human error in its application. PCAST recommends that most of the techniques be put on a more firm scientific foundation, that better proficiency testing be devised for practitioners, and that more objective identification methods be developed.