DETECTING LIES

The Lieutenant Governor of Virginia went on record reiterating his claim the incidents of sexual conduct reported by several women were consensual. He bases his emphatic position on the fact he passed a lie detector test administered by a top-notch examiner. That's not nearly good enough.

The gentlemen seems to misunderstand what a lie detector really does.

Despite the popular name, lie detectors don't detect lies. They detect increased levels of stress experienced by the person "on the box" as certain questions are asked. For this reason, law enforcement personnel refer to the device as a polygraph machine, not a lie detector.

Levels of stress are determined by an increased rate of breathing, elevated heartbeat and blood pressure, and changes in skin conductivity. It's these multiple squiggly lines that qualifies the device as a polygraph.

Stress can be caused by a number of things. Asking a woman to give her age and weight could easily produce a failed polygraph, even if she answers accurately. These particular questions often have increased levels of stress built in.

And by the way, participants will not be asked specific questions like age and weight. The examiner will probably bracket the answer and call for a yes or no response. For example: Are you older than forty? Are you older than forty-five? And so forth, ultimately zeroing in on the correct number.

Because the examiner is looking for a pattern of increased stress leading up to a "money" question, followed by a releasing of stress once the big question is asked, it is imperative the person being tested know all the questions ahead of time.

In fact, the pre-test interview is probably the more important part of the procedure. Detecting "lies" is not a "gotcha" operation. Fateful questions are embedded in the list, surrounded by control questions the subject should be able to answer without much thought. The examiner works his way up to the crucial point, then backs off. Also, the most important questions are often asked multiple times during the session, revealing several bouts of rising and lowering tension.

Knowing the list of questions ahead of time produces anticipation which enhances the level of stress as the test rolls forward.

Obviously, subjects are likely to show little stress when stating what they think to be true. Some nervousness may be expected when approaching the crucial points, but it won't be much, and repetition is likely to dampen the effect.

If the Lieutenant Governor is convinced the sexual encounters were consensual, he will likely pass a polygraph. Doesn't mean a thing.