His job is to separate truth and lies

By CARL HAMILTON
Cecil Whig

ELKTON (AP) — Half of the people James Green meets at work are lying to him.

Dealing with dishonest people is all part of a day’s work for Dfc. Green, a polygraph examiner with the Cecil County Sheriff’s Office.

It’s Green’s job to discern if criminal suspects and job applicants are being deceptive during their interviews. Familiar to anyone who’s ever watched a police drama on television, a polygraph exam, or lie detector test, involves wired gauges attached to the subject’s body.

Those gauges provide Green with an array of physiological data, including constant readings for blood pressure, heart rate and breathing.

“When you lie, your sweat glands secrete,” Green said. “Your body’s reactions deviate from the norm” when you’re lying.

‘TV is fake’

However, unlike the polygraph exams administered in most television shows, there isn’t a dramatic spike on the readout whenever a person gives makes a false statement, Green said.

In fact, he works almost exclusively with computers and typically doesn’t access the data until after the interview.

“Everything you see on TV is fake,” Green said. “Just because you see an increase in a rate doesn’t necessarily mean there’s a deception. It’s not as simple as putting your hand in a barrel and it comes out either clean or dirty. You have to look at it in context with all the other data.”

Green said that in real life being a polygraph examiner is somewhat tedious.

“This would be boring to most people, like watching paint dry, but I love it,” he said.

Green became the polygraph examiner for the sheriff’s office in November 2008 after completing 500 hours of training required as part of a three-month course offered by the Maryland Institute of Criminal Justice.

In addition to learning how to operate the polygraph machine, which he calls “the instrument,” Green studied psychology and physiology.

Green said that since starting the job he has conducted about 100 polygraph tests, which involve monitoring a person while they answer questions for 30 to 45 minutes.

About 60 percent of the people he has tested were job applicants for the sheriff’s office or other police agencies in the area. Green asks them standard questions designed to determine if an applicant is qualified to serve as a police officer. Some of the questions are intended to determine whether the applicant has a criminal record or a history of involvement in criminal or immoral activities.

Hours of preparation

The rest of the people tested by Green have been suspects in criminal cases. He said those tests tend to be far more tedious because the questions he asks are tailor-made for each case. As a result, a great deal of research and consultation is required before the suspect is ever hooked up to the polygraph.

“From start to finish, four to five hours is the average,” Green said, referring to the preparation, testing, data analysis and post-test interview that go into each case.

Green said he first consults with the investigators who are seeking to have a suspect tested.
“I may determine that a polygraph is not appropriate at this stage,” he said.

If Green concludes that a polygraph test is warranted, he then studies all available case files before designing questions that apply to that specific case.

“Every case is unique,” Green said.

After studying the files and developing his questions, Green then conducts a pre-test interview.
After conducting the actual exam, Green will review all of the readings and analyze the data. He then conducts a post-test interview that, in part, further explores answers that raised red flags.

“We don’t split hairs over a big lie or a little lie,” he said. “A lie is always the opposite of the truth. The average human lies seven times a day.”

It’s Green’s job, however, to determine if a person has lied to conceal the truth.

Tests can lead to confession

“Sometimes a post-test interview is a post-test interrogation,” he said. “I’ve had them fail the test and then confess and go on to be indicted and convicted.”

A suspect in a criminal case can’t be forced to take a polygraph test.

“I’ve have examinations with an attorney’s wish and against an attorney’s wish,” Green said, adding that suspects sometimes go against the advice of their lawyers.

Results of a polygraph test can’t be introduced as evidence at trial, regardless of whether they help or hurt a defendant, Green said.

A lie detector test can, however, give investigators insight into an account of an event provided by a suspect, Green said.

When used in conjunction with evidence and statements from other people, the polygraph can help investigators determine whether to pursue criminal charges, he said.

“It is just a tool,” Green said.