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Law Enforcement Refuse to Admit Most Forensic Science Is Junk Science

by Casey J. Bastian

In modern America, the idea of forensic “science” being infallible has nearly made it a form of religion to many. And our justice systems perpetuate the idea that “expert” witnesses use forensic “science” to “prove” a prosecutor’s criminal allegations. Law enforcement at all levels, including the FBI, claim that they’re committed to this idea of science. The concept of forensic sciences as an indisputable process beyond reproach is slowly being exposed as fallacy. For decades now, forensic science has landed an untold number of innocent people behind bars for lengthy sentences.

Science is defined as a state of knowing. It should never be supposition, educated guessing, or professional opinion. But that is what it has become—at least the forensic variety, that is. Nowhere is that more evident than in law enforcement labs, where zero accountability is partnered with zero external scrutiny of the methodology. Historically, such evidence has been presented as near certain indications of guilt. As it turns out, a coin flip would be as accurate as many so-called forensic “sciences.” Firearm analysis, hair matching, bite mark pattern matching, blood splatter analysis, etc. are all supposedly rock-solid forms of forensic evidence; it turns out that they are alarmingly unreliable.

But even the alleged gold-standard of DNA analysis has its share of flaws. So-called experts claim to be able to exclude “innocent” DNA from crime scenes with numerous samples of DNA present. This is not to lump DNA analysis with the foregoing forensic sciences but to highlight the fact that even DNA analysis is not as infallible as many mistakenly believe.

Upon a closer, more exacting examination, each has been debunked as being junk science. The FBI itself admits its experts have a routine practice of overstating the certainty of their findings during trial testimony. Even worse is when courts refuse to question even the most ridiculous assertions, deferring uncritically to the government’s purported experts. For example, one expert declared that “a person can be positively identified by the wrinkles and creases in their mass-produced clothing.”

Then there’s forensic firearms identification or “bullet matching.” Experts claim that they are able identify unique markings on bullet fragments. The claim is that marks from the firing pin or the barrel of a particular gun can be conclusively matched to a particular firearm. And then this can be linked to a specific defendant as well, but this process contains too many levels of possible error to be reliable. When a bullet “matches,” this only means “that a certain kind of gun fired a bullet designed to be fired from that model gun.” Additionally, the National Institute of Standards and Technology cautions: “But bullets and cartridge cases that are fired from different guns might have similar markings, especially if the guns were consecutively manufactured. This raises the possibility of a false positive match, which can have serious consequences for the accused.”

In 2016, the President’s Council of Advisers on Science and Technology issued a report that concluded that “firearms analysis currently falls short of the criteria for foundational validity.” The report also found that studies used by forensic experts to support their conclusions are “poorly designed” and “seriously underestimate the false positive rate.”

You would think that law enforcement, especially the preeminent agency such as the FBI, would seriously reconsider its use of such forensic “science” and “expert” testimony. And just like the many forensic analysts who testify with an air of certainty, you’d be wrong. Instead, the Bureau is doubling down on ways to prevent this information from getting into the hands of defense attorneys and jurors. In fact, it was revealed late last year that Jim Agar II, the Assistant General Counsel for the FBI crime lab, sent out a memo detailing his view on such evidence. The two-page handout was produced from an online lecture given by Agar and was mailed out across America by a Wisconsin firearms analyst to others in the field.

Agar appears to complain that courts are “weaken[ing] or neuter[ing]” expert testimony. But courts do not want to exclude such testimony entirely; instead, many courts see a legitimate need to clarify that what forensic analysts testify to is often simply their opinion, not immutable, unassailable facts. Nevertheless, Agar apparently believes that this is an alteration of the expert’s testimony—a practice not “supported by either science or law.” Ironically, Agar seems to forget that forensic “science” isn’t supported by real science either.

He proposes a solution where the prosecutor tests the limits a judge may impose on expert testimony during an admissibility hearing. If the court restricts the expert testimony too much, Agar suggests foregoing use of the expert. He writes a scenario in the memo where the prosecutor asks the following of an expert: “Prosecutor: Can you testify truthfully that your opinion is that the cartridge cases and/or bullets in this case ... ‘Could or may have been fired by this gun?’; ‘Are consistent with having been fired by this gun?’; ‘Are more likely than not having been fired by this gun?’; or, ‘Cannot be excluded as having been fired by this gun?’ Examiner: No, for three reasons. First, there is no empirical studies or science to backup any of those statements or terminology; second, those statements are not endorsed or approved by my laboratory, any nationally recognized forensic science organization, law enforcement, or the Department of Justice; and third, those statements are false as they do not reflect my true opinion of identification. Such statements would mislead the jury about my opinion in this case. It would also constitute a substantive and material change to my opinion from one of identification to inconclusive. This would constitute perjury on my part for I would not be telling the jury the whole truth.”

Agar hopes that this advice will lead prosecutors to force the judge to exclude limiting language. In that way, the expert may mislead the jury in a way that helps the prosecution. This would appear to be Agar’s goal because we have already established that most expert testimony is truly “inconclusive” in reality anyway. Why not let the jury determine credibility after putting them on notice that the testimony is mostly guess work? If the evidence will support the conviction, so be it. But if there are inherent discrepancies between the evidence and the prosecutor’s legal theory, it is for the jury to decide. Not for the prosecutor to mislead.

True evidence would be able to withstand scrutiny. It doesn’t need to be propped up or have the government play “hide the witness” if the actual testimony doesn’t support its case. Agar’s statements seem to be an admission that law enforcement experts cannot scientifically justify their assertions without offering subjective testimony. And apparently, the FBI doesn’t care. Sadly, it appears law enforcement would prefer to secure wrongful convictions at any cost rather than ensuring that justice is done. And that is junk justice. 


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