Letter from top FBI lawyer tells prosecutors how to avoid judicial review of gun scan


from cheating to win is-how-the-FBI-defines-‘justice’ department

Law enforcement — including the FBI — likes to pretend they’re heavily invested in science. The use of forensic “science” has been with us for years, but nowhere is it more sketchy than in law enforcement labs, where zero accountability sits alongside zero outside scrutiny of methods.

For years, evidence historically considered almost certain clues to guilt has, in many cases, turned out to be no better than a coin toss. Even DNA has its problems, especially when “expert” witnesses exaggerate their ability to exclude “innocent” DNA from cluttered crime scenes. Police reluctance to self-monitor has been compounded by courts’ reluctance to challenge statements made by forensic technicians – those that include things like asserting that a person can be positively identified by wrinkles and creases in his mass-produced clothes.

A judge – Jed S. Rakoff – spoke. He apologized for the DOJ’s review of law enforcement forensics once it became clear the Justice Department was more interested in finding supporting allegations than votes dissidents. The DOJ Deputy Attorney General informed Judge Rakoff that reviewing pretrial evidentiary procedures was beyond the “scope” of the Commission, resulting in Rakoff’s resignation.

Analysis of blood patterns, bite mark patterns, hair matching, etc. Almost every form of supposedly indisputable forensic evidence has been determined to be junk science under further scrutiny. Even the FBI has admitted that its forensic experts routinely exaggerated the certainty of their findings during sworn testimony.

You would think this would all be on top of a major overhaul of forensic procedures and requirements that testing methods must be subject to peer review or blind testing or literally anything else than the zero review they have enjoyed for years. You would be wrong. Instead, agents and law enforcement officials have devoted their energies to finding ways to prevent their unwanted science from being thrown out of court.

A letter obtained by The Daily Beast shows that the FBI would rather lie to the courts than forgo the use of another dubious forensic technique: bullet matching. Investigators say the bullet fragments contain unique markings from the barrel of the weapon they were fired from and that these can be used to uniquely identify the weapon used to fire the bullet. This, of course, assumes that there are no similarities between mass-produced weapons and mass-produced bullets that could result in “matches” that say nothing more than a certain type of weapon has fired a bullet designed to be fired from this model of weapon.

This purported form of evidence has been questioned by the Obama administration:

The most damning criticism of the field came from a 2016 report by the Presidential Council of Advisors on Science and Technology, or PCAST, which found that “firearms analysis currently does not meet the criteria for valid fundamental” and that the study studies practitioners in the field. often cite to support their work are poorly designed and “seriously underestimate the rate of false positives.”

Following this report, some judges began to push back against this dubious evidence. Law enforcement pushes back, led by none other than a high-ranking attorney representing the FBI’s forensic team.

Late last year, a Wisconsin firearms forensic analyst emailed a remarkable document to more than 200 of her colleagues across the country. It was a document from an online lecture given by Jim Agar, the assistant general counsel for the FBI Crime Lab.


In the two-page document, Agar tells gun analysts how to circumvent judges’ restrictions on unscientific testimony. He even suggests a dialogue for prosecutors and analysts to recite if challenged. More controversially, Agar advises analysts to tell judges that any effort to limit their testimony to allegations backed by scientific research is tantamount to asking them to commit perjury.

The letter [PDF] is quite the read. The FBI attorney refuses to even consider the idea that bullet-matching forensics might be flawed. Instead, he asks prosecutors and expert witnesses to work together to undermine any attempt the court (or defense attorneys) might make to paint those findings as dubious. This begins by implying that the courts are wrong to even question the expertise of forensic technicians.

So far, no court has excluded the testimony of an expert witness in gun identification. The greatest likelihood is that the court will attempt to compromise and craft some kind of language that weakens or neutralizes the identifying opinion of the expert, substituting this terminology for the identifying opinion of the examiner. Some courts have put in place so-called “limits” on this testimony, which fundamentally alter the opinion of the examiner. However, these are not real limitations because they make material and substantial changes to the expert’s testimony. These are crude attempts to rewrite expert firearms testimony by a layman with no background in forensics. This practice is not backed by science or law.

And he ends by suggesting that forensic experts not testify fully rather than have their expertise and statements challenged:

If the court insists on limiting expert firearms testimony to RCMP or class characteristics, I probably won’t call the examiner at all. Instead, I would call an ordinary witness such as the case officer or a police department armourer to testify about the similar class characteristics of the weapon and the bullets and/or casings.

Does this sound like science to you? Anything backed by real science might survive the challenges of proof. Since it’s not, it’s not strong enough to survive even a cursory examination. Any business based solely on this shoddy science should be doomed. But by forcing the court to abide by the FBI’s terms (or, conversely, preventing the forensic expert from being interviewed), the agency can still roll the dice by circumventing scrutiny with its means and methods.

The problem for the FBI now is that this letter is in the public domain. Judges attentive to these issues will know exactly why the prosecution is asking leading questions of its forensic expert or why no forensic expert is called to testify. This letter alone should result in the immediate rejection of most firearms scans. It probably won’t, but it should be, unless the law enforcement agency can definitively demonstrate that it uses methods not used by the FBI or that it completely ignored the FBI attorney’s suggestions.

Actual evidence should be able to survive scrutiny. He should be able to stand up without the prosecution playing “hide the witness”. This letter is a tacit admission that gun analysis is more guesswork than science. As such, it should be considered damning evidence in itself – something that will compel law enforcement experts to thoroughly and scientifically substantiate their claims. And that should certainly encourage the DOJ to consider ending the use of gun forensics until it can find a scientifically sound way to do so. But, if history is any indicator, the DOJ prefers to score cheap wins that use forensic evidence backed by solid science.

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Filed Under: evidence, fbi, forensics, junk science


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