Humans are shockingly bad at telling whether or not someone is lying. That’s why, a century ago, psychologists and criminologists developed machines to detect lies for us, by measuring blood pressure, pulse, and breathing rate. Their lie detectors promised to revolutionize the criminal justice system. But is it really possible for science to separate truth from lies?You can binge all episodes of American Innovations exclusively and ad-free on Wondery+. Find Wondery+ in the Wondery App or on Apple Podcasts.See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.