Two hollow tubes wrapped around my chest and abdomen are measuring my breathing, a blood-pressure cuff is tightly encircling my left arm, and moisture-detecting electrodes are secured to two fingertips on my right hand.

A Vancouver detective hooked me to a polygraph instrument, and I discovered I cannot lie. At least not convincingly.

Before getting to the bells and whistles of the LaFayette LX-4000, the instrument used by detectives at the Vancouver Police Department and the Clark County Sheriff’s Office, let me acknowledge polygraph results are not typically admissible in court and there are critics who dismiss the test as junk science.

Nonetheless, both departments use the test for pre-employment screening as well as in criminal cases, and tests are regularly given to convicted sex offenders to ensure they aren’t looking at child pornography or abusing children.

A 2003 study by the National Academy of Sciences found that while polygraphs are “well below” perfect, they are still the best truth-seeking tool available. Another technique, a voice stress analyzer, was banned by the U.S. military in 2006 after studies showed it as reliable as a coin toss, 50-50. Research continues on using expensive magnetic resonance imaging, or MRI, technology, which is based on an idea that we use different areas of our brain when we lie and when we tell the truth, and examiners could see on the MRI which part of the brain is being utilized.

But the polygraph remains king.

The tests are widely used, said New York polygraph expert Joel Reicherter, and thanks to their role as pop culture props (in “The Moment of Truth,” Fox’s latest offering in public humiliation, for example) are misunderstood.

The instruments are nicknamed “lie-detector tests” but don’t detect lies, per se. They can’t read your mind.

If they could, Reicherter said, “then we could close all the courts and fire all the lawyers.”

Reicherter also corrected me when I said “polygraph machine.”

It’s an “instrument,” he said.

“A machine does work for you, like a lawn mower,” he said. “And an instrument collects data.”

Reicherter, 66, has a master’s degree in physiology and is professor emeritus at State University of New York-Farmingdale. He’s an adjunct instructor at the Defense Academy for Credibility Assessment, operated by the federal government at Fort Jackson, S.C.

He said data collected by the LaFayette LX-4000 is recorded by three attachments (arm cuff, tubes and electrodes) and a thin chair cushion that picks up if the person is trying to “beat” the test by clenching muscles. The collected data is fed into the examiner’s laptop computer (those clunky analog machines, with the moving needles and spooling paper, are relics) and charted. The program includes a comprehensive database of medications that affect the test, so those can be factored.

The electrodes, which can be clipped on fingertips or be in the form of two gel pads that are stuck on a palm, have been shown to be the most reliable marker of duress, Reicherter said. When sweat glands become more active, they send an electrical signal recorded by the instrument.

“The theory is that if a question presents a threat to you, you’ll sweat more in preparation of defending yourself,” he said. The subtle increase in perspiration isn’t detected by the subject, however.
“It’s not like sweat running off your forehead on a hot summer day,” Reicherter said.

In addition to perspiration, the examiner looks for other signs of the “fight or flight” response that kicks in during high-stress situations: Is the person’s heart beating faster? Is their breathing more shallow?

Tips for trying to beat the test are available online, and they center on consciously changing your breathing and heart rate. “Think of things that make you ecstatic, fearful or frustrated,” one tipster advises. Or bite your tongue or insert a tack in your shoe — anything to cause pain.

Examiners have heard these “tips” and watch for signs that people are using them.

“The average person looks quite foolish, because they are relatively easy to detect,” Reicherter said. Well-rehearsed guilty subjects might attain a score of “inconclusive,” but it’s difficult to “pass,” he said.

‘Can’t define repulsion’

The polygraph is most accurate — up to 93 percent — when people are asked specific questions about incidents, and details are ones only the guilty person would know, Reicherter said. So when he first saw commercials for “The Moment of Truth,” when contestants are asked questions such as “Are you repulsed by fat people?” his reaction was that the show was hogwash.

“That’s not a polygraph test question. You can’t define repulsion,” he said.

Contestants’ responses are measured against ones they gave pre-show. But trying to tell if a person is lying about a subjective opinion isn’t why the polygraph was made, he said.

The instrument also wasn’t made to ask people about what might happen one day, said Detective Steve Norton of the Vancouver Police Department. Norton has been a certified examiner since 1993. After he retires this year, he will administer tests in private practice.

He was watching promos for “The Moment of Truth” and laughed at questions such as “Do you think you will still be married in five years?”

“(The test) was designed to measure events that have happened. It’s not designed to predict the future,” Norton said.

Flunking the test

Norton and fellow VPD detective Aaron Holladay work at the Children’s Justice Center, where they quiz suspects in sex abuse cases. Detective Rick Buckner administers tests for the Clark County Sheriff’s Office. All three said the first thing they do is to ask general questions to put people at ease.

“Everyone who comes through the door, I expect them to be nervous,” Buckner said. “We all have that fear of the unknown.”

“You certainly want the person to be comfortable,” Holladay said.

Holladay, who took polygraph training two years ago, gave me my test. He told me to pick a number between one and eight and write it down on a Post-It note. Circle the number and think about it, then hide it beneath your right leg, he told me. Then, he said, answer “No” to each question.

He went through the numbers, waiting 25 seconds between each question: “Did you write the number one?” “Did you write the number two?” etc.

When he asked, “Did you write the number six?” I tried to stay calm. “No,” I said, trying to keep my voice steady.

It was no use.

Holladay called me out.

Turns out my perspiration, even though my skin was dry, gave me away. That jagged line on his screen peaked when I lied. My breathing was also transparent. Holladay pointed to the line that showed him I let out a sigh of relief before he inquired about numbers seven and eight, when I knew I didn’t have to lie again.

The detectives weren’t surprised I couldn’t lie about something as stupid as a number. 

We’re raised as children that we should tell the truth, Buckner said. You can’t suddenly believe it’s OK to lie.

“Inside, your heart knows the difference,” Buckner said.

Stephanie Rice can be contacted at 360-735-4549 or stephanie.rice@columbian.com.