Why does the father of the lie detector regret it?

To catch a liar, the ancient Chinese would sometimes fill the accused with raw rice during interrogation, then ask them to open their mouths. Dry rice indicates that the mouth is also dry. This was seen as evidence of criminal anxiety – sometimes becoming grounds for execution.

Many people have long believed that lying has physical side effects, and one man thought he had discovered the science of lie detection in the 1920s, amid crime. boom. This was the period when America banned the sale of alcohol and smuggling gangs were highly active.

Some police departments apply increasingly drastic measures to force suspects to tell the truth, such as beatings, burns with cigarettes, and sleep deprivation. Although contrary to the law, these measures are still common in the United States and have resulted in many confessions, many of which are of questionable accuracy.

August Vollmer, chief of the Berkeley, California Police Department, thought that a new era could be ushered in in which science would make the interrogation process more precise and humane. He began recruiting college graduates to help professionalize the police force. This resonates with John A. Larson, who recently received a doctorate in physiology from the University of California Berkeley and has a passion for justice. Larson joined the Berkeley police force in 1920, becoming the first recruit in the area to earn a doctorate.

Vollmer and Larson were particularly interested in a simple polygraph test created by William Marston, a lawyer and psychologist. Larson attempted to create a much more complex test. He experimented in a university laboratory with a strange combination of pumps and gauges attached to the human body via bracelets and chest belts.

Larson’s device will measure changes in heart rate, respiration and blood pressure simultaneously while a subject is continuously questioned and monitored. He believed that the device would detect incorrect answers through special fluctuations engraved by a pen on a rotating roll of paper. The operator will then analyze and interpret the results.

In the spring of 1921, Larson introduced the psycho-heart-lung machine, later called the polygraph. The machine looks like a combination of a radio set, a medical stethoscope, a dental drill, a gas stove and more, all placed on a long wooden table. The machine attracted great attention and was widely reported Examiner praised: “All liars, no matter how clever, will perish.”

Larson himself doesn’t entirely believe the hype. As he tested the invention, he discovered an alarming error rate and became increasingly concerned about its official use. And although many police departments across the country accept the device, judges are more skeptical than Larson.

In 1923, the US Court of Appeals for the Washington DC Circuit declared lie detector results inadmissible at trial because the tests were not widely accepted by the experts involved. However, the police continued to use the machine. Larson was even disappointed when a former colleague patented an updated version in 1931.

While Larson’s original machine gathered dust, imitators developed many more modern versions, all of which followed the same specifications as Larson’s – and millions were tested. During the Cold War, the US State Department used lie detectors to remove people suspected of being unfit from the federal government. Many innocent employees lost their jobs, while others – later discovered to be dissidents, including the famous spy Aldrich Ames – fooled the tests.

Larson earned a medical degree and spent the rest of his life working as a psychiatrist. However, he was always sad about the lie detector. He describes the device as his “Frankenstein’s monster”, which cannot be controlled or destroyed.

In 1988, the US Congress finally passed a law banning private employers from requiring polygraph tests, although some government agencies still use them for screening and may be used by police on suspects. as an investigative tool in certain cases.