Forensic sciences like DNA, fingerprint analysis, hair analysis, gunshot residue testing, bitemark analysis etc – has long been assumed to be the best evidence in determining whodunit in a criminal case. Aside from DNA, however, it’s becoming pretty clear that most forensic science disciplines aren’t science in that they’re not underpinned by scientific principles. The FBI has backed abandoned many forensic science techniques it long lauded as good policework – like bitemark analysis, hair analysis, etc – are actually junk science. And don’t even get me started on “scent lineups” and other “smell evidence.”

DNA and fingerprints, however, have continued to stand as being considered reliable. Well, hold that thought, because a really interesting article in the Intercept brings fingerprint analysis into question as well. As the article explains, the entire legitimacy of the field of “science” rests on a premise that’s not even proven (that all fingerprints are unique). Beyond that, however, there are other problems.

The National Academy of Sciences report made a host of recommendations for shoring up the validity and reliability of forensic practices. While some practitioners have effectively stuck their heads in the sand, a number in the fingerprint community have heeded the calls for reform by investigating what leads to errors, trying to devise error rates for the discipline, and conducting research into objective techniques for doing their work. Meanwhile, the academy also made a series of broader recommendations, including that crime labs be accredited and practitioners certified and regularly tested for proficiency.

One of the biggest issues was suspiciously high proficiency rates. If someone has been certified as an expert in a field of science, then supposedly their education and training should set them apart from th rest of us. But what does it say about their supposed expert status when pretty much everyone who takes the test to be certified as an expert passes? Going back decades the pass rate for these exams has been in the high 90’s, meaning pretty much everyone passes. In fact you have to go back to 1995 – 24 years ag0 – for a test that tripped up a lot of fingerprint examiners.

The Intercept article is detailed and should make you question whether the fingerprint examiners testifying in your jurisdiction really know what they’re talking about. And whether you’re the accused, a juror, or just someone in the community, that should scare the hell out of you.

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