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The federal government is throwing the book at one of the most vocal critics of the polygraph test. Doug Williams is facing trial on charges of witness tampering and mail fraud. He makes his living teaching people how to beat the polygraph. But his supporters say he's being punished by a government that is overly dependent on those lie detectors. NPR's Martin Kaste reports.
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DOUG WILLIAMS: Are you scheduled to take a polygraph test? Let me give you something to think about before you take it.
MARTIN KASTE, BYLINE: Meet Doug Williams, the self-appointed scourge of the polygraph industry. This is from a video on his website.
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WILLIAMS: I am the only licensed polygraph examiner to ever tell the truth about the so-called lie detector. A polygraph is not a lie detector. Truthful people are often branded as liars and liars often pass easily.
KASTE: For decades, Williams has been selling his books and DVDs attacking the reliability of the polygraph and teaching people how to prepare for the test. He also offers one-on-one training, and that's how the feds got him. Undercover agents posed as clients - people facing polygraph tests at their government jobs. Investigators say Williams helped them even when they told him that they planned to lie. The government calls that a form of witness tampering. Williams calls the prosecution an attack on his right to free speech.
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WILLIAMS: This indictment is brought simply to punish and silence me because I have the audacity to protest the use of the polygraph.
KASTE: The Justice Department won't comment on the case, but even Williams' fans think he's in trouble.
PETER MOSKOS: Obviously, they want to get him. I think they got him dead to rights, too.
KASTE: This is Peter Moskos, a former cop who now teaches at the John Jay College of Criminal Justice.
MOSKOS: Just 'cause they're getting him and just 'cause he did, perhaps, you know, knowing people were going to line the test, still help them out, that doesn't make the test any better.
KASTE: That's the question that's now being revived by the Williams case. Just how good are polygraph tests? Can you really measure honesty by tracking things like breathing and heart rate? The National Academy of Sciences took a close look at this in the early 2000s. Statistician Stephen Fienberg chaired the review.
STEPHEN FIENBERG: These channels that the polygraph captures, whether it's the sweating on fingertips or breathing, this information does tie in to the notion of lying or deception. Unfortunately, it ties into other things as well.
KASTE: False positives are a big problem, Feinberg says. While the test can catch liars, it also accuses too many innocent people.
FIENBERG: My personal conclusion is that it has no place in government's dealings with its citizens.
KASTE: The defenders of polygraphs actually embrace The National Academy of Sciences review. Raymond Nelson is the president of the American Polygraph Association. He says of course the test isn't perfect, but its accuracy rate is still in the low to mid 80s.
RAYMOND NELSON: That's still better than any other technology available today. And it's still better than trying to make human judgment based on, you know, non-instrumental methods for credibility assessment.
KASTE: The thing is most Americans don't have to worry about the polygraph. Back in 1988, Congress banned private employers from using it on job applicants. But it exempted government, so thousands of federal employees still take it, as do many applicants for jobs with local police departments. That's Peter Moskos hates the test so much. He had to take it when he became a cop in 1999. He passed it by reading up on its flaws. And now that he teaches aspiring police officers, he advises them to do the same.
MOSKOS: I mean, anyone who takes the test, you're a fool if you go into a lie detector test thinking that, yeah, telling the truth is good enough.
KASTE: Meanwhile, the government has increased its dependence on the test. In 2010, Congress expanded the polygraph requirement to Customs and Border Protection. That's now the country's biggest law enforcement agency. That's what sent the wave of new clients to Doug Williams, and it's what caused the subsequent sting operation. Stephen Fienberg, the statistician who led the NAS review of polygraphs, finds the government's reaction to Williams disturbing.
FIENBERG: To think that the government now wants to stop people who are going to help expose its fallibilities is to me pretty ludicrous. That's not what I want government to do.
KASTE: And Doug Williams wasn't an isolated case. A similar sting nabbed another anti-polygraph trainer in Indiana. He got eight months. In both cases, federal investigators got the trainer's client list, including the names of government employees who sought their advice on how to beat the machine - government employees who now have another reason to sweat. Martin Kaste, NPR News.