The Justice Department is squandering progress in forensic science

Imagine this: A cop pulls you over and arrests you because you match the description of someone wanted for a heinous crime. You are innocent, but after being charged and brought to trial, you watch as experts testify with “scientific certainty” that hair and footprints at the scene match your own, and you are led from the courtroom in shackles.

This may seem like a scene straight out of a TV melodrama, but this scenario happens in real life far too often. A number of forensic techniques — including hair- and footprint-matching, mark analysis, bloodstain-pattern analysis and others — lack scientific validity and reliability yet are used frequently in our nation’s courtrooms.