Judges and Science

With all the talk about the importance of science you would think debunked forensic science would receive more coverage. Forensic science can literally be a life or death matter in some states for some crimes. Unfortunately, the courts are setup in such a way that the validity of forensic techniques is not determined by researchers in the field but by men in magic muumuus:

Giannelli, who served on President Barack Obama’s now-disbanded National Commission on Forensic Science, looks at how six forensic fields for which there is little to no supporting scientific research (or in some cases, that scientific research has discredited) — bite-mark comparison, arson, microscopic hair analysis, firearms and toolmark analysis, fingerprint analysis, comparative bullet-lead analysis. These fields vary in scientific credibility and probative value from little to none (bite-mark comparison and bullet-lead analysis) to possibly valuable, though the extent of which is still unproven (fingerprint analysis).

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But it’s quite a bit worse than that. The fact is, judges continue to allow practitioners of these other fields to testify even after the scientific community has discredited them, and even after DNA testing has exonerated people who were convicted, because practitioners from those fields told jurors that the defendant and only the defendant could have committed the crime. In the few fields where the courts have finally admitted that they got it wrong, for the most part there has been little effort to systematically review all of the cases that those mistakes may have affected. It has largely been left to defense attorneys and nonprofit legal groups to find those defendants and file claims on their behalf.

Of course, none of this should be surprising. We don’t ask judges to perform regression analyses. We don’t ask them to design sewer systems, hit fastballs or compose symphonies. We know they aren’t qualified to do any of those things. Judges are trained to perform legal analysis. No one goes to law school to become a scientist.

Judges should not be expected or even allowed to decide what types of forensic science are valid and what types are invalid. They lack the training and the background to determine such things. However, I’d hazard a guess that few in the legal system have any interest in putting qualified people in charge since that would likely reduce conviction rates and therefore cut into the State’s profits.