Why a High-Ranking FBI Attorney Is Pushing 'Unbelievable' Junk Science on Guns

[Celerity]

Forensic analysts testify at trials as “experts.” But juries don't know that their methods "seriously underestimate the false positive rate.”

https://www.thedailybeast.com/the-fbi-keeps-pushing-junk-science-to-win-convictions



Late last year, a forensic firearms analyst in Wisconsin emailed a remarkable document to more than 200 of her colleagues across the country. It was a handout from an online lecture given by Jim Agar, the assistant general counsel for the FBI Crime Lab. For years, forensic firearms analysts have claimed the ability to examine the marks on a bullet found at a crime scene and match it to the gun that fired it—to the exclusion of all other guns. It can be powerfully persuasive to juries. But over the last decade or so, some scientists have cast doubt on the claim.

Forensic firearms analysis falls into a subcategory of forensics colloquially known as “pattern matching.” In these specialties, an analyst looks at a piece of evidence from a crime scene and compares it with a piece of evidence associated with a suspect. The most damning criticism of the field came in a 2016 report by the President’s Council of Advisers on Science and Technology, or PCAST, which found that “firearms analysis currently falls short of the criteria for foundational validity,” and that the studies the field’s practitioners often cite to support their work are poorly designed and “seriously underestimate the false positive rate.”

After decades of deferring to these forensic analysts, a handful of judges started to heed the warnings from scientists, and have put limits on what some forensic witnesses can say in court. Those decisions have sparked a defensive backlash in the forensics community, along with rebukes from law enforcement officials and prosecutors. Agar’s document is part of that backlash. In the two-page handout, Agar instructs firearms analysts on how to circumvent judges’ restrictions on unscientific testimony. He even suggests dialogue for prosecutors and analysts to recite if challenged. Most controversially, Agar advises analysts to tell judges that any effort to restrict their testimony to claims backed by scientific research is tantamount to asking them to commit perjury.

Agar’s document was so volatile, it was upbraided by the Texas Forensic Science Commission (TFSC). That agency—the only one of its kind—was formed in the wake of revelations that bogus expert testimony likely caused the state to convict and execute an innocent man, and is tasked with ensuring that expert testimony given in Texas courtrooms is scientifically valid. The TFSC called Agar’s advice to firearm analysts “irredeemably faulty,” and stated that it “runs counter to core principles in science.” “This is just really unbelievable,” Ellen Yaroshefsky, a professor of legal ethics at Hofstra University, told The Daily Beast after reviewing Agar’s memo. “He’s encouraging false testimony and he’s undermining respect for the judiciary. I mean, he’s saying that if a judge says you can’t give unscientific testimony, you’re being forced to commit perjury? It’s just absurd.”

A Short History of FBI Forensic Blunders.......

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[Scrivener7]

1. This is stunning. There is a book called The Cadaver King and the Country Dentist

that talks about forensic methods that have always been considered scientific and how absolutely unscientific they are. Bite mark analysis is a big one.

There is also an issue with autopsies in general. In some places it has been made into a racket, and the results are completely undependable. Reports are simply made up and evidence is destroyed or manufactured to the specifications of local law enforcement.

Really frightening.