Flawed Hair Evidence Tainted 1970 Murder Conviction
A 50 year old murder conviction was reversed by the United States Court of Appeals for the District of Columbia Circuit based on the use of discredited hair analysis testimony at the trial.
Almost fifty years ago, appellant Dennis Butler was convicted of murder. At his trial, an FBI forensic expert testified that hairs found on the victim were microscopically identical to Butler’s hair. The government recently acknowledged, though, that hair evidence of the kind introduced against Butler was false and exceeded the limits of science, and that the prosecution knew or should have known as much at the time of his trial.
Butler brought a motion to set aside his conviction and vacate his sentence based on the government’s admission that it had used false evidence against him. We examine a single question: whether the false hair evidence presented by the government was material. The district court found the evidence immaterial. In our view, however, there is a reasonable likelihood that the false hair evidence introduced against Butler could have affected the jury’s verdict. We thus reverse the judgment of the district court.
The majority opinion was authored Chief Judge Srinivasan joined by Circuit Judge Pillard.
For decades, the FBI Laboratory employed a form of forensic analysis dubbed “hair microscopy.” Hair microscopy called for forensic examiners to conduct side-by-side, microscopic comparisons of hair samples in an effort to ascertain whether hairs from a crime scene matched hairs from a suspect. The government used ostensible matches at trial as scientific evidence linking defendants to crimes.
There was, however, a significant problem with that field of analysis: science had not validated its foundational premises. Existing studies failed to support a trained examiner’s ability to identify a “match” based on any objective system of visual hair comparison or to validly estimate the frequency of hair characteristics (and therefore of matches) in the general population.
Although those limitations were long known to the government, prosecutors continued to rely on hair evidence at trial. By 2009, however, multiple developments spurred the government to reassess its position on the evidentiary reliability of hair microscopy. First, the National Academy of Sciences published a groundbreaking report critical of the practice. The report confirmed that “[n]o scientifically accepted statistics exist about the frequency with which particular characteristics of hair are distributed in the population,” and noted the absence of any uniform standards for identifying how many characteristics must be shared between two hairs before they can be called a “match.” Nat’l Research Council, Strengthening Forensic Science in the United States: A Path Forward 160 (2009). Additionally, DNA testing exonerated several men who had been convicted using hair evidence, some of whom had been imprisoned for decades.
Those events prompted the federal government to undertake its largest postconviction review in history. Working in tandem with defendants’ rights groups, the government audited thousands of convictions from the pre-2000 period to identify cases in which the government made use of false hair evidence. This is one of the identified cases.
A dissent
KATSAS, Circuit Judge, dissenting:
My colleagues set aside a half-century-old murder conviction based on a few scraps of misleading testimony that were briefly given and immediately corrected. In so doing, they recast Napue v. Illinois, 360 U.S. 264 (1959), which permits relief only if there is a reasonable likelihood that false testimony caused a conviction, into a hairline trigger for setting aside convictions. And they downplay untainted evidence that overwhelmingly establishes the defendant’s guilt. For both reasons, I respectfully dissent.
(Mike Frisch)