CRF Blog

Man vs. Machine

by Bill Hayes

In Man vs. Machine, a Bloomberg Businessweek feature story looks at an ex-cop’s battle against the polygraph, or lie detector.

The quest to defeat lying is as old as humanity. In Bronze Age China and India, suspects had to chew uncooked rice and spit it out to reveal if their mouths were dry. Medieval Europe had trial by fire or water. In the 1950s and ’60s, the CIA experimented with LSD as a truth serum. Then there’s torture, formalized in ancient Greece as a method to compel honesty and recast for the 21st century as “enhanced interrogation.”

The polygraph, invented in 1921, is today’s most widely trusted lie-detection device. It’s used to determine who gets hired by the CIA, the FBI, the Drug Enforcement Administration, and police departments all over the country. It helps decide who gets security clearances. Police detectives use it as an investigative tool, intelligence officers use it to assess the credibility of sources, and exams are commonly required as a condition of parole and probation for sex offenders.

This reliance continues despite the lack of scientific agreement about how well — or even whether — the polygraph works. Defenders point to studies that show a 90 percent accuracy rate. The National Academy of Sciences, however, in a 2002 report, found a “lack of understanding of the processes that underlie polygraph responses” and concluded that the quality of polygraph research “falls far short of what is desirable.” These criticisms, according to many psychologists, remain true. Some of the nation’s most notorious spies, including Aldrich Ames and Ana Montes, passed polygraphs. In a 1998 Supreme Court decision, Justice Clarence Thomas wrote, “There is simply no consensus that polygraph evidence is reliable,” and most judges have agreed.

For three and a half decades the polygraph has had no critic more dedicated or more obstreperous than [Doug] Williams. He’s been a White House aide, a private investigator, a construction worker, and a member of the clergy. In the 1980s he was a barnstorming activist living out of a truck, giving talks and training sessions, going on talk radio and TV, testifying in courtrooms and before Congress. He eventually settled down and began charging for his instructional materials and tutoring. Over the past few years he’s learned, painfully, what can happen when an obsession becomes a business — especially when that business is spreading detailed information about a law enforcement technology that works best when its subjects know only what they’re told. [more]