“Junk science” isn’t limited to the non-FDA approved supplements that claim one drop of their magical secret formula will make you bigger, stronger, faster, taller, smarter, and happier. As it turns out, much of the police work on shows like “CSI” has about as much validated scientific research behind it as the latest too-good-to-be-true scientific breakthrough to hit the late-night TV informercial circuit.
The most recent example of made-for-tv forensic evidence that has failed to meet scientific rigor is “toolmark” evidence. That is, the idea that it is possible to see the marks that something like a wire cutter left on a wire and say definitively that the wire must have be cut by the wire cutter found in the defendant’s garage by a comparison of the two.
In the recent case People v. Genrich, the Colorado Court of Appeals considered a challenge to a 1991 conviction based on a 2009 report by the National Academy of Sciences that found that toolmark evidence is, at its core, junk science. An ATF agent had testified at Mr. Genrich’s trial as a toolmark expert, claiming he could match specific tools that had been found by police to marks on parts of a homemade bomb.
At the time, such expert testimony was widely accepted in criminal trials. Yet according to the National Academy of Sciences and the supporting affidavit of one of the key scientists behind the report, these “expert” opinions were completely lacking any scientific studies that validated the underlying principles or the ability of any expert to make a definitive match. Faced with such strong evidence that a long-accepted field of forensic science was junk, the Court of Appeals granted Mr. Genrich an evidentiary hearing to challenge his conviction.
“Toolmark” evidence not the only area of widely accepted forensic evidence that has had its scientific validity — whether that being the underlying methods, or the application to a particular case — come under scrutiny. In a famous example, the FBI arrested and held an American lawyer whose fingerprints “matched” those found at the scene of a bombing in Madrid, only to find that the match was objectively wrong. Follow up research found a high probability that any fingerprint would show as a match to at least one of the 470 million fingerprints in the FBI database, even in situations where the “match” was thousands of miles away at the time of the crime.
Colorado has seen is own share of scandals with forensic evidence. In 2013, the Colorado Department of Health and Education laboratory that was responsible for testing blood samples for drugs and alcohol shut down amid allegations of failing to meet critical testing standards and an intentional bias to find results that were best for the prosecution. In 2015, the Colorado Bureau of Investigation was found to have provided inaccurate results in numerous cases. In 2017, a former employee came forward with evidence that the signatures on the certificates certifying many of the Intoxilyzer-9000’s – the machine used across the state to test suspected drunk drivers’ breath for alcohol- had been forged, calling into question the machines’ accuracy.
Those faced with criminal allegations based on “junk science” find themselves in a very difficult position. Prosecutors will argue that “The science doesn’t lie!” and that the jury must convict based on the facts that are beyond dispute. But sometimes the science does lie- and when it does, the only defense is an experienced attorney who knows how to teach a jury to separate out the “junk” from the truth.