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Science & sorcery in forensic DNA evidence

M.W. Perlin, "Science & sorcery in forensic DNA evidence," Science in our world: certainty & controversy, Penn State Beaver, Monaca, PA, 7-Apr-2017.

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Forensic DNA evidence is only as good as the statistical science that underlies its conclusions. However, crime laboratories often cannot accurately interpret the DNA mixtures that comprise most biological evidence. As a result, their match statistics may be incorrect or go unreported. This scientific failure harms innocent victims and criminal justice.

The talk describes the DNA controversy, and how a naive desire for certainty harms forensic science. Laboratory failure is illustrated in a double homicide case that might have been prevented using better DNA methods. The speaker expresses the harm inflicted on society by unscientific data "thresholds" in a live performance of his song Threshold.

The talk is one in Penn State Beaver's new "Science Series" on scientific controversy and certainty, co-sponsored by the Brodhead Cultural Center and Academic Affairs. The series, spun out of a spring honors class that examines science in the news, invites three experts to talk about science and how it impacts our world.