This FBI dog hair scandal should make us question our faith in scientific evidence

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In 1978, Santae Tribble, then 17, was convicted of a murder in D.C. based on the testimony of two FBI forensics experts. They asserted that a single hair strand found at the crime scene matched Tribble’s DNA. He served 28 years in prison before an independent analysis found that the hair was no match—it was a dog’s hair.

Tribble was exonerated, but his case is one among potential thousands of individuals convicted on the highly questionable FBI hair forensics practices. As Fusion’s Daniel Rivero reported this week, “over 95 percent of the cases involving hair evidence that the FBI has reviewed so far contained flawed testimony—257 out of 268 cases.”

Consistently racist and ubiquitously prosecution and conviction driven, investigators wield the power society accords them as experts, often with scant regard for consequences of their “facts” for the condemned. But there’s more than pernicious police work at play here. There’s a problem—a deep, philosophical problem—of how we think about science and truth.


The FBI witnesses presented their testimony as fact. In Tribble’s case, it was bullshit—DNA analysis found it was a dog’s hair. But, and this is crucial, by the scientific paradigms of the day, the hair forensic testimony was fact. And it got to be a fact, and sent a man to jail, because the science of the time has purview over the production of facts. Trusted scientific fields are always regimes of expertise—systems of authority, hierarchy, and control. And the FBI witnesses had dominion over facts in that courtroom. As if scientific knowledge floats above systems of power and oppression.

We have an entire pop-cultural genre which helps edify the idea that police science and criminology is the work of pure, unbiased discovery. This is the conceit of TV comedy-drama Bones, a show that paints forensic anthropology as unfettered mystery solving with science. Or the dozens of “gotcha” moments peppering series like CSI and Law & Order, in which to obtain DNA evidence is to have found the truth. We forget that in most of these plots, we’re coaxed to side with the fictional cops, and put faith in their drives towards prosecution as reliable searches for justice.


But cop shows tend to treat cops like they treat scientific evidence: as unique, honest, and distinct from the systems in which they would be situated IRL. Luckily, and increasingly, we see such pop-cultural elevation of cops as fatuous. Our believe in the infallibility of contemporary science, especially police science, however, remains problematically based in a fiction.

A near-religious belief in modern science-as-objective truth means that we view our given terrain of facts, managed and controlled by experts, as proven, discovered truths. Science doesn’t do this ever: rather, the power structure we call scientific knowledge determines the field of what might count as evidence, and the method by which facts are established. These regimes of expertise, regimes of truth in Michel Foucault’s terminology, produce the terrain of things that get to be facts in a given point in time. That’s what I mean when I say that science produces truth, it does not discover it. We can say things are true and are scientifically proven—that’s fine, so long as we recognize that proof and truth always exist within systems, which can and often should be challenged.


In 1978, it got to be fact that the hair at the crime scene belonged to a 17-year-old black man. In a new regime of scientific truth production, this was no longer a fact. It was a dog’s hair. This is not simply a case of the better science of DNA-analysis winning through. Crucially, groups like the Innocence Project do the work of challenging the claims made by police and FBI experts. DNA-analysis is the tool du jour, and an important one, but only in so far as it is wielded as a weapon against our racist, vicious criminal justice system.

If we celebrate DNA-based exonerations as primarily a victory of scientific progress, we forget that this current science can be used by pre-existing power structures to control and oppress. DNA-databases, for example, are a vast work of fact production: the fact of individuals deemed suspect and criminal in perpetuity. No science does neutral work.


Phrenology, the study of skull shape to determine a person’s character, laid the very framework for biological criminology; a fierce scientific racism asserted facts about the criminal skull, a pseudo-science precursor to the continuing profiling of the criminal black man. Eugenics is a science too, which once commanded dangerous consensus. It’s a banal point to highlight history’s wealth of dangerous scientific paradigms. But we should not be so foolish to think we have attained some pure criminology, absent scientific pretexts used to uphold systems of oppression.

Without improvements in DNA forensic sciences, the FBI’s decades of hair forensics convictions could not be challenged. And if the set of facts produced by DNA-analysis means that fewer humans are in cages, then this is indeed progress to be celebrated. Yet, often the only way to successfully undo the problematic facts produced by one revered science is to rely on scientific progress; to find better evidence to highlight bad evidence, to pull out the dog hairs. So it matters all the more to recognize that established power structures—within government, law enforcement and the academy—control the productions of truth which can condemn a person to prison or death, shielded from responsibility by pointing to infallible science.


Access to scientific expertise is protected and reserved for the privileged. But there is no mythic force of scientific progress that will deliver justice. The lesson of the FBI hair scandal is that authority must be challenged, especially when it’s parading as truth.