April 12, 2000

Searching for the truth

Polygraph examiner uses instrument to separate fact from fiction

By Garret Leiva
Herald editor
       Barefaced lies, a lie in one's throat- even the occasional white lie, Thomas Keith has heard every one. After all, it is his job.
      As owner of Keith Polygraph and Investigative Services, this state licensed examiner has administered thousands of polygraphs. While the questions change from case to case, nearly thirty years later Keith is still seeking the same answer: the truth.
      "I am trying to find what the truth is, not deception; there is a difference," noted Keith, who runs a polygraph service in Traverse City and an investigative office in Battle Creek.
      Since the late 1960s, Keith has been involved with law enforcement, including two years with the Grand Traverse County Sheriff's Department. "Interrogation and interviews have always fascinated me," said Keith, a former detective with the Eaton County Sheriff's Department.
      This fascination with finding the truth brought Keith to the classroom in 1975. His American Institute of Polygraph Technology and Applied Psychology program consisted of nine weeks and 360 resident academic hours. Enrollment in the state certified training school also included a six month internship an excess of 150 polygraph examinations.
      As both a public and private examiner, Keith conducts specific issue polygraph examinations. His polygraph resume includes examinations of suspects, witnesses, victims involved in criminal investigations and subjects of internal investigations. Further experience includes court testimony in reference to examinations conducted as well as polygraph procedure and admissibility.
      He also conducted preemployment polygraphs until the Employee Polygraph Protection Act of 1988 prohibited most private employers from using tests to screen applicants.
      Learning to tell a well-told lie from the truth requires an understanding of both human nature and analog machinery.
      According to the American Polygraph Association, the term "polygraph" literally means "many writings." The name refers to the manner in which selected physiological activities are simultaneously recorded.
      A polygraph instrument will collect physiological data from three systems of the human body. Convoluted rubber tubes that are placed over the examinee's chest and abdominal area record respiratory activity. Two small metal plates, attached to the fingers, record sweat gland activity and a blood pressure cuff records cardiovascular activity.
      Keith noted that a polygraph examination consists of three phases: pre-test, instrument and post-test data analysis. In the pre-test, Keith reviews the examinee's health history and outlines the testing procedure. Unlike most tests, those taking a polygraph know the questions in advance.
      "There are no tricks or surprises," Keith noted. "The only thing you've got to worry about is that if you lie to me I'm going to know it."
      To ensure he arrives at the truth, Keith makes sure he asks the right questions along the way. During the course of a two hour examination, Keith uses highly structured relevant, irrelevant, symptomatic and control questions. Each of the 12 to 13 questions is answered with a simple 'yes' or 'no' response.
      "Polygraphs work on a fear-threat factor. We are taught that if you get caught telling a lie you can be punished," Keith said. "I assure you that by the time I get you in that chair, with those attachments, you're going to realize that very clearly."
      Separating fact from fiction is part of the job for a polygraph examiner. That also includes sorting real life and Hollywood movie scripts.
      "When they show a shot of the instrument, that's pretty accurate," Keith wryly noted. "Then they start asking questions like, 'What did you do last night?'"
      Another myth Keith readily dispels is the notion of 'beating a polygraph.' If a person knowingly perceives to tell a lie, Keith said, physiological factors occur in the body that can not be controlled. "Tell your heart to stop - you can't. Autonomic responses are what we deal with in polygraph," he said.
      While it's nearly impossible to alter physiological responses, that hasn't stopped some examinees from trying. Keith has heard it all, from mind-altering drugs, to putting a penny in your mouth or a tack in your shoe.
      "All you will get is a bad taste in your mouth (or) a hole in your foot and probably a bad infection," said Keith, who once had a suspect fall out of the examination chair after overdosing on Valium ingested in the bathroom prior to the polygraph.
      That is not to say Keith and his polygraph have never been fooled. While running a test on a 16-year-old suspect in a criminal sexual conduct case, Keith determined the boy was telling the truth. A separate police polygraph test also confirmed those findings. When the DNA evidence came back, however, the suspect was a perfect match.
      "It turned out that the boy had a twin brother the defense attorney didn't know about - guess who took the polygraph?" Keith said.
      For nearly a quarter of a century, Thomas Keith has searched for the truth. Finding the answer isn't always easy, nor is telling the whole truth and nothing but the truth.
      "I had to take a polygraph test prior to entrance into polygraph school. I was so nervous, I told them everything in the world," Keith remarked.
      "I sat there and worried about anything I had ever done, including the nickel bubble gum cigar I stole from the neighborhood dime store when I was nine years old ... and I had gone back and paid for it the next day."