Anyone who watches dramatized detective shows–especially those of the CSI variety–knows that the real starring role is played by technology: cool, highly sophisticated devices that virtually no real-life crime lab can afford. These shows are fun, but accuracy isn’t the strong suit of storylines that need to be resolved in an hour’s time. (Fingerprint identification isn’t the slam dunk that Abby’s computer makes it seem on NCIS.)
Even the popular culture shows that don’t rely on “gee whiz” gadgetry, however, routinely use lie detectors. So the general public can be forgiven for thinking that lie detectors work.
They don’t. At least, not reliably. As Morton Tavel has noted
In 2003, the National Academy of Sciences (NAS), after a comprehensive review, issued a report entitled “The Polygraph and Lie Detection,” stating that the majority of polygraph research was “unreliable, unscientific and biased”, concluding that 57 of approximately 80 research studies—upon which the American Polygraph Association relies—were significantly flawed. It concluded that, although the test performed better than chance in catching lies—although far from perfect—perhaps most importantly, they found the test produced too many false positives.
In other words, nervous people who are telling the truth can easily fail the test. And many do.
This lack of reliability is widely understood in the legal community and among police officers; it’s why most courtrooms don’t admit lie detector results into evidence. It’s also why several ex-police officers have spoken out against their use, and why a subset of them has helped job applicants and others who face “screening” by detectors learn techniques that will help them pass.
And that brings us to a fascinating question. Is helping people pass a lie detector test a crime? What if you aren’t just helping Nervous Nellie tell the truth in a way that won’t trip the machine, but you are helping Sneaky Sam lie?
Douglas Gene Williams, a former Oklahoma City police polygraphist and the proprietor of Polygraph.com, has been teaching individuals how to pass polygraph tests since 1979. He has recently been indicted for mail fraud and witness tampering for allegedly “persuad[ing] or attempting to persuade” two undercover agents posing as customers “to conceal material facts and make false statements with the intent to influence, delay, and prevent the testimony” of the undercover agents “in an official proceeding….”
Williams’ defenders say this is entrapment, that the attempt to shut him down is implicit acknowledgment that the tests don’t work, and that Williams has a free speech right to criticize their use by demonstrating their manifest unreliability. Others–including many polygraph critics and yours truly–say that helping guilty people fool the tests goes beyond advocacy, and is a bridge too far.
What say you?