State v. Alexander

Thomas Alexander (defendant) and a co-defendant, each separately charged with sexually abusing a minor, hired the same polygraph expert who was prepared to testify to a 90% likelihood both had truthfully denied the abuse; at a consolidated admissibility hearing, dueling experts agreed polygraphs measure some physiological response to lying but disagreed on various reliability factors, including that control-question polygraphs were more prone to false positives than false negatives and that certain evasion techniques (learnable online in under an hour) could reduce accuracy substantially. The judges found the polygraphs reliable enough under Daubert, treated the identified problems as going to weight rather than admissibility, and conditioned admission on the defendant submitting to a second polygraph by a state-chosen examiner and testifying at trial subject to cross-examination; the co-defendant later failed his state polygraph and pleaded guilty, and both the defendant and the prosecution appealed the admissibility ruling.