THE UNCERTAINTIES OF DNA EVIDENCE.

THE UNCERTAINTIES OF DNA EVIDENCE. Matthew Shaer has an article in the Atlantic (June 2016) and Peter Andrey Smith has an article on the Smithsonian site (June 1, 2016) on evidentiary problems with DNA. Some of the mistakes and miscarriages of justice that they describe are—despite the scientific breakthroughs underlying DNA evidence—examples of “low tech” evidentiary mistakes. Shaer begins with a horror story about a conviction based on bungled lab work in a Houston case. For openers, the lab worker had come up with three different DNA profiles for the victim (!) based on three samples of blood or saliva from the same person (the victim). Shaer also tells the story of Dwayne Jackson, who served time because a lab had accidentally switched his DNA with that of the actual culprit. And DNA, like other forensic evidence, can be affected by perverse incentives. Shaer points out that: “In North Carolina, state and local law-enforcement agencies operating crime labs are compensated $600 for DNA analysis that results in a conviction.”