(Click on image to enlarge). The Federal Bureau of Investigation has for­mal­ly acknowl­edged that exam­in­ers from the FBI Laboratory’s micro­scop­ic hair com­par­i­son unit for decades pro­vid­ed flawed foren­sic tes­ti­mo­ny pur­port­ed­ly match­ing crime scene hair evi­dence to the hair of defen­dants charged with those crimes. As part of an ongo­ing review of inac­cu­rate foren­sic evi­dence, the FBI admit­ted that, in the 268 tri­als exam­ined so far, its foren­sic experts sys­tem­at­i­cal­ly over­stat­ed the cer­tain­ty of match­es between crime scene hair evi­dence and defen­dants’ hair. That flawed tes­ti­mo­ny favored pros­e­cu­tors more than 95% of the time. 

The FBI admit­ted pro­vid­ing inac­cu­rate expert tes­ti­mo­ny in 32 cap­i­tal tri­als in which defen­dants were sen­tenced to death, includ­ing 10 cas­es from Florida and 5 each from Pennsylvania and Texas. Nine of the defen­dants — includ­ing all 5 from Texas — have since been executed. 

Studies have shown that inac­cu­rate foren­sic evi­dence is fre­quent­ly present in inno­cence cas­es — and improp­er hair com­par­i­son tes­ti­mo­ny may already have con­tributed to at least one wrong­ful exe­cu­tion. Senator Richard Blumenthal, a for­mer pros­e­cu­tor, said, These find­ings are appalling and chill­ing in their indict­ment of our crim­i­nal jus­tice sys­tem, not only for poten­tial­ly inno­cent defen­dants who have been wrong­ly impris­oned and even exe­cut­ed, but for pros­e­cu­tors who have relied on fab­ri­cat­ed and false evi­dence despite their inten­tions to faith­ful­ly enforce the law.”

The FBI and the Justice Department said they are com­mit­ted to ensur­ing that affect­ed defen­dants are noti­fied of past errors and that jus­tice is done in every instance. The Department and the FBI are also com­mit­ted to ensur­ing the accu­ra­cy of future hair analy­sis tes­ti­mo­ny, as well as the appli­ca­tion of all dis­ci­plines of forensic science.”

The report like­ly cov­ers only a frac­tion of affect­ed cas­es, as many more are still under review, and FBI exam­in­ers trained hun­dreds of state and local crime lab ana­lysts in the same flawed tech­niques. (Click here to enlarge image.)

Citation Guide
Sources

Spencer S. Hsu, FBI admits flaws in hair analy­sis over decades, The Washington Post, April 18, 2015; Image cred­it: Washington Post.

See Innocence and Arbitrariness.