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

In this fascinating look at the history of lie detectors, Wired reporter Katwala (Quantum Computing: How It Works and How It Could Change the World) explores how American law-enforcement came to place its faith in them. In 1921, San Francisco police chief August Vollmer learned of experiments to detect lies by measuring blood pressure. He recruited officer John Larson, who had degrees in physiology and psychology, to build on those experiments. Aided by Leonarde Keeler, Larson invented a device that translated blood pressure measurements into written lines, to be analyzed after a subject was asked a series of questions. It was seized on by Vollmer as a breakthrough, but as Katwala shows, it led to significant false conclusions, as there “is no way for an examiner to be sure whether a change in blood pressure is due to fear of getting caught or anxiety about being falsely accused.” More recently, lie detection technology has expanded to include processes “powered by brain scans and artificial intelligence” that have been “greedily adopted by police forces and governments, drawn in by the false promise of a machine that tells the truth.” Katwala has real storytelling chops, and the chilling conclusion about the flawed nature of polygraphs truly hits home. This evocative account complements Ken Alder’s The Lie Detectors: The History of an American Obsession. Agent: Kris Dahl, ICM Partners. (Mar.)