For over a century, we've been inventing technology to catch liars in the act. To this end, the polygraph was invented and became wildly popular in the mid-20th century. Then, there was an era of "micro-expression training," which claimed person could be caught lying through a skilled analysis of their face. Now, there's talk of using artificial intelligence to analyze the human voice. But do any of these methods even work? And if not ... what are the risks? Emily and Gina investigates how deception research has changed and why it matters. Check out our episode page, where Emily linked to the experts she talked to and the papers she discussed.Got another human behavior you want us to investigate using science? Email us at shortwave@npr.org — we'd love to hear from you!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy