BROOKE GLADSTONE: On January 14th, in the waning days of the Bush administration, Principal Deputy Assistant Attorney-General Steven G. Bradbury issued an opinion that an old memorandum regarding the use of the polygraph machine in the executive branch had no legal standing. The memo was penned by President Lyndon Johnson who forbid his staff from using the machine in employment and personnel investigations. He said, quote, “I am convinced that action is necessary to prevent unwarranted intrusions into the privacy of individuals.” But we long to intrude, and technology joined the effort in 1913, when a Harvard psychology student named William Moulton Marston used systolic blood pressure as a form of lie detection. Incidentally, he also invented the DC Comics character Wonder Woman, whose magic lasso had the power to force anyone encircled by it to tell the truth.
[WONDER WOMAN THEME SONG UP AND UNDER] Her lasso probably worked better. A 2003 report by the National Academy of Sciences found that though polygraph tests work better than random chance, they should not be relied upon for screening security personnel. The NAS also suggested that it's the polygraph’s mystique, rather than its scientific foundation, that accounts for much of its success. That may be why Jerry Seinfeld failed the test he took to prove to his girlfriend that he'd never watched Melrose Place.
[CLIP FROM SEINFELD]
POLYGRAPH OPERATOR: What's your name?
JERRY SEINFELD: Jerry Seinfeld.
POLYGRAPH OPERATOR: Did Billy sleep with Allison's best friend?
JERRY SEINFELD: I don't know.
POLYGRAPH OPERATOR: Did Jane's fiancé kidnap Sydney and take her to Las Vegas, and if so, did she enjoy it?
JERRY SEINFELD: Yes!
[LAUGHTER] Yes. That stupid idiot! He left her for Kimberly! He slept with her sister!
BROOKE GLADSTONE: Jennifer Mnookin is a professor of law at the University of California in Los Angeles. She told us back in 2006 that the courts have almost uniformly rejected the testimony of the polygraph. Still, we feel the allure of a lie detector, even though stone cold liars, like the real-life spy Aldridge Ames, or crazy people, can often find their way around it.
JENNIFER MNOOKIN: Psychopaths will be precisely the ones who can beat the machine. And certainly, in the NAS report about the polygraph, which mostly focused on the employment and security setting, pointed out that if anyone's going to have the incentive to study how to beat the machine, it's going to be people engaged in treason and deceit. But, you know, it's still widely used as an interrogation technique by the FBI, by local police departments. And, interestingly, they don't want it to be admitted into evidence because if it were to be regularly admitted by courts, they'd have to answer to legal standards. Now they can choose how to administer the tests and, in the words of one FBI polygraph expert to me, it's a confession-producing machine.
BROOKE GLADSTONE: [LAUGHS] Well, explain how it’s used in that context then.
JENNIFER MNOOKIN: I think a big part of it is about making the suspect believe in the machine, and once the suspect believes in it, then often, whether or not the machine works, they make the decision to confess, to tell the truth. You know, there's apocryphal stories about sometimes police investigators using other machines, claiming that they're lie detectors, and psyching the suspect into believing that the machine will be able to see whether the suspect is telling the truth.
BROOKE GLADSTONE: You've written about how '40s crime films began to reinforce this myth of infallibility, and you talk about a movie called Call Northside 777, starring Jimmy Stewart, in which the polygraph decides a case.
RICHARD CONTE AS FRANK: Keep away from Keeler and that lie detector.
JAMES STEWART as P.J. McNEAL: I'm not afraid of it.
RICHARD C: That's what I said --- that was a cinch. Then they talked me into going up against that box.
JAMES STEWART AS P.J. McNEAL: Well, what happened?
RICHARD CONTE AS FRANK: What do you mean, what happened? I'm doin’ life, ain't I?
JENNIFER MNOOKIN: The polygraph test is set up in the film as a virtually infallible truthtelling device. And, interestingly, in the movie, they had Leonard Keeler, who was one of the inventors of the polygraph, play himself [BROOKE LAUGHS] to give it a certain kind of verisimilitude. Depictions like that in the film had cultural effects that would lead people to have eve more belief in it.
JIMMY STEWART AS DETECTIVE McNEAL: Would you be willing to take a lie detector test?
RICHARD CONTE AS FRANK: Mr. McNeal, for 11 years I've been waiting for a chance to get at that box.
JIMMY STEWART AS DETECTIVE McNEAL: You know what you're up against? If it turns out bad, you're cooked.
RICHARD CONTE AS FRANK: I'll take the test.
BROOKE GLADSTONE: The media love to report when polygraphs are being used. Scott Peterson took it in connection with his wife's murder. The Ramseys took it in connection with the JonBenet Ramsey case. Do you think that news outlets generally are sufficiently skeptical about the polygraph?
JENNIFER MNOOKIN: Well, I think you're right that suspects sometimes wield their willingness to take it as itself a mark of innocence, and that itself, regardless of what the machine ends up showing, reveals something about my belief in my own honesty.
BROOKE GLADSTONE: Jennifer Mnookin is a professor of law at the University of California, Los Angeles.