Tremors in the Blood: Murder, Obsession, and the Birth of the Lie Detector

In this true-crime thriller, award-winning journalist Katwala (The Athletic Brain: How Neuroscience Is Revolutionising Sport) offers a detailed history of the polygraph, showing how it has been used—and misused—since its creation. In the early 1920s, San Francisco police chief August Vollmer was genuinely interested in new and innovative ways to improve policing. When he read about experiments in which blood pressure changes indicated a person was lying, he recruited John Larson to build a “lie detector.” Larson, unlike most police officers of his era, had attended college, earning degrees in both physiology and psychology. Larson constructed a machine that successfully tracked blood pressure measurements on paper, but this flawed device almost immediately showed reliability issues, despite Vollmer’s claim that it was a “breakthrough.” Narrator Paul Bellantoni strikes the perfect conversational tone—with just a dash of noir detective—drawing listeners into the details of the 1920s crimes and criminal investigations while also clearly presenting Katwala’s extensive research.