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‘The Lie Detector’ dives into the history of the polygraph

Popularly known as the “lie detector,” the polygraph seized headlines and was extolled in movies, TV and comics as an infallible crime-fighting tool


Adrian Gomez
Albuquerque Journal

ALBUQUERQUE, N.M. — As a filmmaker, Rob Rapley knows that each project brings on a new challenge.

When the story about the history of the lie detector crossed his path, he knew he would be interested.

Little did he know that he would be consumed with the subject for some time.

"(The subject) offers more than meets the eye,” he says. “It seems small at first, but the history moves so fast. It keeps going and reveals a lot about ourselves.”

Rapley says his wife works in public radio and the story was mentioned.

“I’m interested in science and history and the intersection of the two,” he says. “This one has a very particular history.”

Rapley’s completed documentary is set to premiere on PBS at 8 p.m. Tuesday, Jan. 3, on New Mexico PBS, channel 5.1. “The Lie Detector” is branded under the American Experience umbrella. It will also stream on the PBS Video app.

“The Lie Detector” begins in the first decades of the 20th century, when life was being transformed by scientific innovations, researchers made a thrilling new claim: they could tell whether someone was lying by using a machine.

Popularly known as the “lie detector,” the device transformed police work, seized headlines and was extolled in movies, TV and comics as an infallible crime-fighting tool.

Husbands and wives tested each other’s fidelity.

Corporations routinely tested employees’ honesty and government workers were tested for loyalty and “morals.”

But the promise of the polygraph turned dark, and the lie detector too often became an apparatus of fear and intimidation.

Rapley says today the lie detector is little more than a curiosity to the general public. But for decades, the device was an inescapable feature of American life, used by police, the government, the CIA and the FBI, and more than half the retail businesses in the country.

“Designed to ferret out Communists, cheats, criminals and homosexuals, it was used on millions of ordinary people, changing tens of thousands of lives forever,” he says. “Yet in most of these circumstances, the results were little better than guesswork. Never fully accepted in any other country, the lie detector remains a uniquely American phenomenon.”

In the first decades of the 20th century, three men — police officer John Larson, psychologist William Marston and Larson’s assistant Leonarde Keeler — claimed the polygraph could detect a lie by monitoring the physiological responses of their subjects.

In 1921, Larson — a rookie cop in Berkeley, California, and the only police officer in the country with a PhD — pursued a vision of scientific, clean policing. Determined to find a more humane alternative to the “third degree,” Larson created a device that took continuous blood pressure and respiration readings. When he solved a series of thefts with the device, reporters celebrated his machine as the way of the future.

But Larson later realized his suspect had only confessed to the crime to avoid having her deepest secret — a history of sexual abuse — revealed. Disillusioned, Larson left Berkeley and quit the police.

The lie detector had other champions, including William Marston, inventor of the “Marston Deception Test.” Although this was simply a blood pressure cuff and useless as a lie detector, Marston promoted it as almost infallible. But in a sensational murder case in 1923, an appeals court declared the lie detector inadmissible. With few exceptions, that has been the case ever since.

Marston persevered and within a few years was using his lie detector to compare the emotional responses of blondes vs. brunettes and redheads. Marston’s hair color tests were a joke in the scientific community, but they caught the eye of Carl Laemmle, head of Universal Studios. By 1929, Marston was in Hollywood, tracking the emotional response of test audiences to upcoming releases. Over the years, Marston would use his lie detector for everything from advertising to marriage therapy — always one step ahead of his creditors, and sometimes the law. He finally hit it big when he created Wonder Woman, who fought evil with what became known as “The Lasso of Truth.” He died in 1946 a rich and famous man widely hailed as the inventor of the lie detector.

But it was Keeler, an assistant to Larson, who made the device a common feature of American life. While Larson envisioned the lie detector as a humane interrogation technique, in Keeler’s hands it became a psychological extension of the brutal third degree and the polygraph spread to police departments across the country.

Rapley says with the colorful cast of characters, he wanted to keep focus on the lie detector itself.

“In a way, the media really made this device into something it wasn’t,” he says. “We gave it more power than it should have had. I think people still believe in it because we want it to work so badly.”

American Experience’s “The Lie Detector” will air at 8 p.m. Tuesday, Jan. 3, on New Mexico PBS. It will also be available to stream on the PBS Video app.

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