Polygraphs don’t tell the whole truth — In October of 2019, the Hawai’i Supreme Court ruled that police illegally coerced a confession when they misled a suspect about the results of a polygraph test administered during his interrogation. The problem with the police conduct in this case, however, lies not in their dishonesty but in their use of polygraphs at all. The Court’s ruling leaves unchallenged the belief that pseudoscientific lie detection can contribute reliably to criminal investigations. It in fact reinforces the aura of legitimacy around this practice by suggesting that there would be a proper way to use lie detectors. As a scholar of criminal justice issues for over two decades, I am confident that polygraph tests should play no role in law enforcement.