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When President Ronald Reagan’s White House threatened thousands of government officials with polygraph exams, supposedly to protect classified data (but probably also to control press leaks), his Secretary of State George Shultz threatened to resign.
Reagan’s White House backed down and agreed to impose the tests only for those suspected of espionage, according to a 1985 New York Times report.
In terms of catching spies, polygraph tests failed spectacularly in key moments. More on that in a moment.
First, consider the second Trump administration, which is leaning in on polygraphs, presumably to ferret out leakers, but also as an apparent method of intimidation.
“The polygraph has been weaponized and is being used against individuals who have never had a polygraph requirement, whether pre-employment or security, in their entire federal careers,” said Mark Zaid, an attorney who specializes in representing people who work in national security, after a slew of published reports about polygraph threats throughout the Trump administration.
The tests are frequently being used to identify not leaks of classified information but rather “unclassified conversations regarding policy or embarrassing decisions that have made their way through the rumor mill or directly to the media,” said Zaid, who has previously testified before Congress about the use of polygraphs and sued federal agencies for their practices.
► At the FBI, the New York Times reports, an increased use of polygraphs has “intensified a culture of intimidation” for agents.
► At the Pentagon, officials publicly threatened to conduct polygraph tests as part of an effort to figure out how the press learned that Elon Musk was scheduled to get a classified briefing about China, which a billionaire with business interests in China probably should not get. It’s not clear if polygraph tests were ultimately administered as part of the probe, according to CNN’s report.
► At the Department of Homeland Security, according to CNN, polygraph tests have been used on FEMA and FAA officials in addition to those in more traditional national security roles.
Administration officials have defended the practice as a way to protect government information.
DHS Secretary Kristi Noem defended the use of polygraph tests during an interview on CBS in March. “The authorities that I have under the Department of Homeland Security are broad and extensive,” she said.
Previously, per Zaid, polygraphs have been used as a sort of “weeding device,” not unlike a physical fitness test for large pools of applicants to national security and law enforcement roles. After that, some employees — particularly in the intelligence community — may be given exams every five or 10 years, sort of like a random drug test.
What’s happening now is something different.
Polygraph tests are “being used against individuals who have never had a polygraph requirement, whether for pre-employment or security, in their entire federal careers,” Zaid said.
Most Americans have never been subjected to a polygraph, and that’s in large part because Congress acted to largely outlaw them from use in the public sector in 1988, a time when millions of Americans were being polygraphed each year and companies were using them to bar people from jobs and conduct coercive internal investigations.
For an example of why polygraphs were problematic, look back at an old “60 Minutes” segment in which Diane Sawyer submits to an exam and hidden cameras are used to show how the bias of the examiner affects results.
“If you’re trying to find one leaker in an organization of 100 people, you could end up falsely accusing dozens of people,” according to Amit Katwala, author of the polygraph history Tremors in the Blood: Murder, Obsession and the Birth of the Lie Detector. “And you might not even catch the culprit — there’s no evidence to suggest that an actual lie detector is even scientifically possible,” he told me in an email.
The Employee Polygraph Protection Act was signed into law in 1988 by Reagan, years after his showdown with Shultz. But the law kept polygraphs for the public sector, particularly for national security and law enforcement.
In the national security world, the principle of protecting the innocent is “flipped on its head,” according to Zaid.
“We would rather ruin 99 innocent people’s careers than let the one new Ed Snowden, Aldrich Ames or Robert Hanssen get through,” he said.
If polygraphs have a spotty record in detecting lies, they have a horrible record in detecting spies.
A Senate Intelligence Committee report from 1994 explores how the CIA officer Aldrich Ames, who spied for the KGB, evaded detection for years in part because he passed multiple polygraph exams. At the same time, the same report describes how another CIA employee who aided the KGB, Edward Lee Howard, did so in part because he felt jilted by the CIA after he was fired for failing a polygraph exam.
Then there was the shocking trial of FBI official and Russian spy Robert Hanssen, who had never been given a polygraph in his career, there was an uptick in their use at some agencies, including the FBI and the Department of Energy.
At the turn of the 21st century, the US government commissioned a large-scale report on the efficacy of the polygraph undertaken by a special committee at the National Research Council.
They found the scientific evidence on polygraphs to be more than lacking.
“As a nation, we should not allow ourselves to continue to be blinded by the aura of the polygraph,” Stephen Feinberg, the Carnegie Mellon professor who led the study, testified before Congress.
Ames offered his assessment of the polygraph machine in a letter from prison published in 2000, calling the polygraph “junk science that just won’t die” and saying it is most useful as an instrument of coercion.
“It depends upon the overall coerciveness of the setting — you’ll be fired, you won’t get the job, you’ll be prosecuted, you’ll go to prison — and the credulous fear the device inspires,” he wrote.
Polygraphs are frequently used in criminal investigations, but rarely used in court.
The idea behind the polygraph, which was first developed in the ‘20s, is that lying causes stress.
The examiner hooks a person up to monitors that gauge things like blood pressure and fingertip sweat. A pre-interview helps formulate common questions that create a baseline and reactions to more probing questions are compared to that baseline.
But it’s not a scientific process, and it can be beaten, or misled, since at its core the machine is simply measuring physiological responses. Frequently, incriminating information is offered by nervous exam-takers who don’t understand exactly how the process works.
Pop culture often suggests that when a person is hooked up to a polygraph machine, their lies will be detected. But that is not exactly true.
“The polygraph works because we think it works. It’s a tool of psychological coercion in an already intimidating environment—particularly when it has the weight of the federal government behind it,” Katwala told me.
But the intimidation is probably the point.
“Using the polygraph may not help you catch the leakers, but the idea of it could well scare any potential future leakers into keeping their mouths shut,” Katwala said.
The man credited with fully developing the polygraph, a Berkeley police officer named John Larson, who also had a PhD in psychology, would later turn on his invention as unreliable, according to Katwala.
Larson was inspired by the truth-telling machine of William Marston, himself a psychologist, but one with an active imagination and a flair for the theatrical. Zaid described him as the PT Barnum of polygraphy. Here’s a video of Marston using a polygraph-like machine and claiming to identify the varying emotions of blonde, brunette and redheaded women. His conclusion was that redheads like to gamble, brunettes are looking for love and blondes are easiest to scare. Okay.
Marston also invented the comic book hero Wonder Woman, with her Lasso of Truth.
Katwala warns that there are new technologies being developed with the help of AI or revolving around brain waves, but he argues they should be viewed just with the same skepticism as the polygraph machine.
“None of them get past the Pinocchio’s nose problem — everyone’s different, and something that works for one person might not work for everyone,” he said.
But they could all be used in the same coercive way as the polygraph machine.
