Radley Balko and Tucker Carrington
The Washington Post
Originally posted March 21, 2018
Here is an excerpt:
At the trial level, juries hear far too much dubious science, whether it’s an unproven field like bite mark matching or blood splatter analysis, exaggerated claims in a field like hair fiber analysis, or analysts testifying outside their area of expertise. It’s difficult to say how many convictions have involved faulty or suspect forensics, but the FBI estimated in 2015 that its hair fiber analysts had testified in about 3,000 cases — and that’s merely one subspecialty of forensics, and only at the federal level. Extrapolating from the database of DNA exonerations, the Innocence Project estimates that bad forensics contributes to about 45 percent of wrongful convictions.
But flawed evidence presented at trial is only part of the problem. Even once a field of forensics or a particular expert has been discredited, the courts have made it extremely difficult for those convicted by bad science to get a new trial.
The Supreme Court makes judges responsible for determining what is good science. They already decide what evidence is allowed at trial, so asking them to do the same for expert testimony may seem intuitive. But judges are trained to do legal analyses, not scientific ones. They generally deal with challenges to expert testimony by looking at what other judges have said. If a previous court has allowed a field of forensic evidence, subsequent courts will, too.
The article is here.
Note: These issues also apply to psychologists in the courtroom.