Earlier this month, we looked at a pair of controversial articles published by the Wall Street Journal that addressed a study by the President’s Council of Advisors on Science and Technology (PCAST). The first article, by a judge on the Ninth Circuit Court of Appeals, came out swinging in favor of the report’s findings, questioning forensic evidence techniques and experts in fields such as DNA, fingerprint, firearm, footwear, and hair analysis. The author asserted that these disciplines are “bad science” and “have absolutely no scientific basis,” and that the forensic scientists that practice them are, in summary, incompetent and/or crooked. Predictably, those scientists took a different view of the study and responded in kind to the judge’s argument.
A month later, we’re starting to see the ramifications of that study trickle down from the press into the courtroom. An article in today’s Boston Globe paints an interesting picture of what that looks like in the high-profile murder case of ex-New England Patriot Aaron Hernandez.
As a refresher, the PCAST study questions whether the science of analyzing the types of evidence mentioned above is sound enough to support the standard of proof that is constitutionally required for a criminal conviction. Hernandez’s attorneys jumped at this seed of doubt and asked the judge to throw out expert testimony related to a firearm that police have linked to the case. The motion specifically cites the PCAST report’s recommendation that judges play a bigger role in deciding what evidence should be presented to the jury and instructing the jury of the potential unreliability of these types of evidence. Hernandez’s defense team is essentially asking the judge to follow through on that recommendation by excluding the examination of the gun as evidence.
If the judge in the Hernandez case does toss the firearm evidence, it will contradict another recent ruling that addressed the same issue. In the first case known to consider the PCAST report, a judge in Illinois refused to exclude ballistics analysis, saying that “an independent review of the testing method was sufficient to support the validity of the examination.”
Hernandez’s judge seems to be following a similar process, and has ordered prosecutors to prove that investigators used the level of independent analysis that the PCAST report recommends. How it will play out remains to be seen. The Globe article states that “prosecutors will present the same argument to Locke [the judge] in the Hernandez case: That Boston police conduct a sound scientific method in firearms examinations that was upheld by the courts a decade ago.”
What does all of this mean for expert witnesses and the attorneys who retain them? The waters have become decidedly murkier. While this particular report isn’t the first to question evidence analysis, it seems to be making a significant impact. The tide appears to be turning towards skepticism. For my money, this issue isn’t as black and white as the pure scientific validity of these methods of analysis; what about the value of expert interpretation? But no matter where you stand, it’s never been more important to secure experts that you can trust.