About this episode

This episode explores the history and implications of the polygraph, invented by John Larson in 1921.

The ability to tell if someone is lying has long been something humans have attempted to perfect. From torture to psychology, it is the holy grail of criminal investigation. In 1921, a PhD student and police rookie, John Larson, may have cracked the code by inventing the polygraph. It is an invention, many said, that was sure to change the face of criminology forever. Or maybe not. Did he instead unleash a monster into the world? This is the story of the polygraph. Sources https://www.pbs.org/wgbh/americanexperience/features/lie-detector-1000-words/ https://www.smithsonianmag.com/smithsonian-institution/why-creator-first-lie-detectors-regret-invention-polygraph-machine-inventor-180985222/ https://illumin.usc.edu/lie-detection-the-science-and-development-of-the-polygraph/ Image: https://en.wikipedia.org/wiki/Polygraph#/media/File:Leonarde_Keeler_1937.jpg Sponsor Go to factormeals.com/dispatchespod50off to get 50 percent off and free daily greens per box. New subscribers only. While supplies last until 09/27/2026. (See website for more details). History Dispatches is part of the Airwave Media Network: www.airwavemedia.com Interested in advertising on History Dispatches? Email us at…

People in this episode

Hosts: Matt Breen, McKinley Breen

Topics covered

• polygraph
• lie detection
• criminology
• invention
• psychology

Keywords

• polygraph
• lie detector
• John Larson
• criminology
• psychology
• invention
• truth detection

Sponsors

Factor Meals

Mentioned in this episode

Organizations: Airwave Media Network, PBS, Smithsonian, USC

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