Now that the Modesto, Calif., case involving Laci Peterson has evolved into the latest high-profile murder turned media spectacle, one of the questions surrounding defendant/husband Scott Peterson will likely be this: Why hasn’t he taken a lie detector test to back up that “not guilty” plea?
At this point, we expect such a move. After all, the polygraph has a history of making its way into these crime-of-the-century cases. Lindbergh baby kidnaper Bruno Hauptmann reportedly wanted to take one, but never got the chance. O.J. Simpson supposedly failed his but denied that it ever took place. John and Patsy Ramsey passed one administered under their own terms, as did former congressman Gary Condit – but skeptical authorities questioned the defendants’ home-field advantage in both instances.
As for the public expecting a polygraph to enter the picture once again … well, actual events and those portrayed on television and in the movies – from “Law and Order” to “Meet the Parents” – have teamed up to make that little box of wires a pop culture icon. This, despite the fact that the vast majority of us will never come into personal contact with a polygraph. This, despite the fact that the validity of the process itself has sometimes come under fire.
“Popular culture and the mass media often portray lie detectors as magical mind-reading machines,” the National Academy of Sciences said in a research report released last year. “The mystique surrounding the exams – instead of a solid scientific foundation – may account for much of their usefulness to authorities.”
To be fair, the report also said that in specific event testing, as opposed to general screening, the results are “well above chance, but they are far from perfect.”
What comes across in the media, then, obviously is a lot less complicated than the behind-the-scenes reality of the lie detection business. On TV and on the big screen, results come quickly and are rarely challenged. Accused adulterers get swift justice after being tested on the daytime talk-show carnivals. Criminals break under the polygraph pressure on the nightly detective shows.
“What people are seeing is probably about 80 percent myth and strictly for entertainment purposes,” says Dan Sosnowski, a board member of the American Polygraph Association. “The vast majority of criminal polygraph examinations take anywhere from an hour and a half to three hours. Sometimes longer.”
A correctly administered test also shouldn’t involve multiple questioners and rapid-fire questions, a staple of the fictional lie detector process, Sosnowski says.
Test operator “is key”
What is pretty much true to form, however, is the look of the machine itself. Rubber tubes are placed around the subject’s abdomen and chest, and a blood pressure cuff goes on the arm. Tiny metal plates are clipped to the finger tips. During the exam, the polygrapher records breathing rate, heart rate and perspiration rate. These are measured in response to a series of relevant questions (“Did you harm your wife?”), control questions (“Have you ever harmed anything before?”) and irrelevant questions (“Is your shirt blue?”).
Sosnowski says the accuracy rate of a test designed for a specific incident – say, a murder – is about 94 percent.
“That’s if you follow the rules and the procedures,” explains the former Chicago-area police officer. “The individual giving the test is the key. If that person can’t formulate the proper questions, then the other guy is going to beat him.”
Those formulating the questions will have completed training at one of the approximately 20 schools that the polygraph association recognizes and accredits. As for government regulation, 29 states require a license for operation. Illinois does, Missouri does not. While Sosnowski has a private practice, a large number of polygraphers in the United States work for federal, state and local agencies. Many are hired to do internal screening of employees and potential employees at such places as the FBI and CIA, a process barred in private workplaces by Congress in 1988.
The polygraph screening tests, as evidenced by the NAS report, have regularly come under fire, and even Sosnowski admits that not enough evidence exists to completely support the process: “All our studies and research, for the most part, have addressed criminal type cases.”
Former FBI agent Drew Richardson, now a leading opponent of the polygraph tests that he once researched at the FBI, calls the examinations not only worthless, but harmful.
“Polygraph depends on a universal bluff,” Richardson says. “And that bluff is that there is some diagnostic value to (the test.) Of course, that bluff is continually reduced as people become more aware of the whole thing.”
Those who are aware include some of the testers, adds Richardson, but he feels they ignore this because they see utility in terms of getting confessions.
“Well, in order to do that, you have to maintain this almost comical bluff that it does have meaning – or else nobody would confess to something that didn’t have any.”
“Trickery – not science”
Richardson’s writings and congressional testimony often end up on the Internet site Antipolygraph.org. Co-founded in 2000 by Gino Scalabrini and George Maschke, the site serves as a clearinghouse for news stories and personal testimonials that challenge lie detection’s credibility.
Maschke’s involvement stems from a polygraph test that he says kept him from joining the FBI in 1995. He was accused of deception – a charge he vehemently denies. He soon discovered that others out there shared his fate.
“I think most Americans see the polygraph as I once did: as an admittedly imperfect but nonetheless science-based technique that has some, perhaps even a high degree, of validity,” the Netherlands-based Maschke wrote in a recent e-mail exchange. “We’re trying to change that perception by informing the public about the trickery – not science – behind the polygraph.”