The truth about the polygraph

Why does the Department of Energy want to do polygraph testing if it's junk science? Is it so stupid it doesn't know that?

It is not stupid, though some congresspeople may be.

When the scientists at the nuclear labs went public with their protest against being given polygraphs, retired Air Force Gen. Eugene Habiger, in charge of the DOE's security, told the San Francisco Chronicle that the test is a powerful deterrent.

Polygraphs don't have to work to be a deterrent. People just have to believe that they work and can reveal whether they have committed crimes. The DOE doesn't have to believe they work, either.

More important, polygraphs are an immensely effective interrogation tool; they need not detect lies. Lykken tells an anecdote of two cops interrogating a suspect at a time when copy machines were not familiar objects. Lacking a lie detector, the cops put a piece of paper in the copier that said "He's lying!" They made the suspect place his hand on the strange machine while they asked him questions. When they didn't like his answers, they'd hit a button on the machine. It would groan, whir, stink and shoot out a piece of paper that read "He's lying!" Realizing that denial was useless, he confessed.

"If I was in the police business I would use [the] polygraph," says Lykken. "It's a powerful inducer of confessions, and you don't have to hit 'em with any clubs. I can't blame the police for using it; I only blame them for believing it."

A 1983 report from the Office of Technology Assessment says, "It appears that the NSA [National Security Agency] (and possibly CIA) use the polygraph not to determine deception or truthfulness per se, but as a technique of interrogation to encourage admissions."

The FBI, interrogating Wen Ho Lee in March 1999, told him that he had failed his polygraph tests. He had taken two. The first was given by the DOE in December 1998, and three examiners agreed he'd passed "with flying colors." The DOE apologized.

A few weeks later the FBI said Lee had not passed after all. In February 1999, the FBI retested him. Unusually, they did not say at the time that he had failed, as they later charged. In March 1999, the FBI interrogated him, telling him that he'd flunked both tests. In a standard interrogation technique, they asked him to explain this. "If I don't have something that I can tell Washington as to why you're failing those polygraphs, I can't do a thing," said one agent, according to transcripts.

Lee said he didn't understand. If he didn't explain, said the agent, "I can't do anything for you, Wen Ho." The agent listed the things he couldn't do for Lee unless he explained why he hadn't passed the test: He couldn't get him his job back, keep reporters from calling his family, keep his wife from being given a polygraph or keep "them" from going to Lee's house and taking him away in handcuffs. Lee repeated that he was telling the truth.

The agents then pointed out that they also wouldn't be able to keep Lee from dying in the electric chair like Julius and Ethel Rosenberg if he didn't tell them why he had failed the polygraph test. "They electrocuted them, Wen Ho."

If Lee is really a spy, he might know how to fool the polygraph test. Lykken is confident that a spy would have received the simple training required to beat the polygraph.

Spies Aldrich Ames and Harold J. Nicholson passed routine CIA polygraph exams. In fact, it's not clear that any spies have ever been caught by polygraph testing. "It's inconceivable that [a spy] won't know how to beat the test," Lykken says. "So the spy won't be caught, and a few innocent people will have their careers ruined, and the secretary of energy will say that we did everything we could. I think it's a scandal."

Was Lee telling the truth? DOE polygraph examiners thought he was truthful in December 1998. Then the FBI said the same test results showed that he failed. When they interrogated Lee, agents told him he had failed both that test and the later FBI test. Did he really fail? Since polygraph examiners often disagree with one another (and even with their earlier diagnoses), the question is not very meaningful. Neither is the question of whether the agents genuinely thought that he'd failed, since even if they believed he'd passed, telling people they've failed is such a powerful interrogation technique.

Could polygraphs ever work? All they do is record certain poorly correlated physical reactions to mental stimuli. Since people don't think and react identically, since even when we're being offensively honest we don't always agree about what is the truth and what is a lie, the attempt seems doomed by definition.

What if polygraphs worked perfectly, if they could somehow sort out the tension caused by telling lies from the tension caused by fear of being called a liar, and could do it every single time? What if they never made an innocent person look guilty, never let a guilty person get off and could always tell who was likely to steal from an employer or betray the employer's trust? What if two examiners never reached different conclusions from the same charts and the same examiner never read the same chart two different ways? Would that change everything?

Those who administer polygraphs would be even more impelled to hook people up. But many people would be just as eager not to be hooked up, even if they weren't guilty of crimes and didn't plan to be guilty of crimes in the future. Do we want government minions or corporate flunkies reading our minds and feelings? The American Civil Liberties Union has called polygraph tests "strip searches of the mind."

We would have people flying about demanding to be hooked up and answer just one question: "I did not break your Lego tower, I swear. I demand a lie detector test!" "I did not think you were stupid for acting that way at the party, honestly. How can I convince you? I'll gladly go on the box!"

We would also have people carrying polygraphs around with them at all times: "You really believe people pick up their welfare checks in Cadillacs? Put these electrodes on and say that!"

Lee, on trial not for spying but for mishandling classified data, is in solitary confinement in a New Mexico jail. He is the only person to be prosecuted for such offenses. Some angry scientists have pointed out that former CIA Director John Deutch committed a similar offense in keeping classified material on unprotected home computers. He lost some of his security clearances, but not others, enabling him to do lucrative consulting.

Many of Lee's colleagues view him as a hapless scapegoat who made serious errors. "What he is accused of is a very serious security violation," says electronic engineer William O'Connell, a past president of the Society of Professional Scientists and Engineers (SPSE). "There may be some real spy problems," he adds, saying that he favors improved computer security, "but there's no evidence to connect Wen Ho Lee to those issues."

The charges that Lee was singled out because of his ethnic background, charges supported by statements made by several DOE officials, are also creating great unhappiness in the labs.

At this writing, the DOE has redefined the category of those who must be given polygraphs to scientists in a few highly sensitive categories, reducing the number from 13,000 to 800. It has also said it will ask Congress to soften its mandate that the DOE do polygraph testing. These steps have muted the storm, but opposition remains. The SPSE continues to take the position that no one should be subjected to the voodoo vagaries of the polygraphs, and to fret that the DOE still has the power to order sweeping testing at any time.

In a recent criminal investigation of the murder of an LLNL worker, Livermore police, who apparently haven't been following the news, were surprised by the unwillingness of many of the worker's colleagues to undergo polygraph testing.

As for the future of the polygraph, although it has almost been banned from private business, it continues to find a home in various arms of law enforcement. Its popularity there may rest less on any misguided belief in its infallibility than on its real efficacy as a tool of interrogation.

Yet the tide may be slowly turning. The 1988 Employment Polygraph Protection Act dealt the industry of pre-employment screening a serious blow. The gradually increasing body of research has convinced scientists that the polygraph is a form of interrogation, not science. But as long as general public awareness of the subject is uncritical, spy scandals will be followed by politicians calling for testing so they can be seen taking action and by law enforcement calling for testing in hope of extracting confessions.

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