The Truth About Polygraph Tests
They’re junk science, inadmissible in court, and about as reliable as a pack of Tarot cards.
Claire Berlinski
September 19, 2018 Technology and Innovation
News organizations would render a valuable service if, whenever they report that someone has taken or proposes to take a polygraph, they reminded readers (or explained to them) that polygraphs are voodoo. Junk science. They are no more reliable than a pack of Tarot cards. Polygraph evidence is inadmissible in court. There is a good reason for that. To check Brett Kavanaugh’s qualifications for the Supreme Court, Congress would do well to ask him whether he believes Frye v. United States and United States v. Scheffer were correctly decided. This would be far more illuminating (and meaningful) to anyone trying to discern his qualifications for the Court than asking him whether he assaulted Christine Blasey Ford.
Journalists who report that Mike Pence has offered to take a polygraph (to prove that he was not the author of the anonymous New York Times op-ed), or that Ford has taken one, without explaining that polygraphs cannot discern truth from falsehood are wasting an opportunity to educate their readers. If you promulgate the idea that there’s a machine that can tell when someone is lying, you shouldn’t be surprised to find yourself living in a culture so hostile to science that kids go unvaccinated and measles break out in the First World.
A polygraph measures your heart rate, breathing, and galvanic skin response. There is no evidence that any pattern of physiological responses is unique to deception. Polygraphs are useful to investigators trying to elicit a confession, however: if you convince suggestible people that these measurements are associated with lying, they are more likely spontaneously to confess when you tell them, “The machine says you’re lying.â€
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https://www.city-journal.org/truth-about-polygraph-tests-16180.html
