The FBI announced this week it will review thousands of old cases – some involving the death penalty – in which forensic specialists used hair samples to help gain convictions. At least 2,000 cases from 1985 to 2000 will be reviewed, and at least 27 involve the death penalty. In some cases, the convicted defendants have died in prison. The study will focus on whether analysts exaggerated the significance of their hair analyses or reported them inaccurately. Defendants will be notified and free DNA testing offered if errors in lab work or testimony are detected.

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And in the Washington Post here