Polygraph Examiners

There are only two people in the room during a polygraph exam -- the person conducting the exam and the subject being tested. Today, some polygraph examiners prefer to be called forensic psychophysiologists (FPs). Because polygraph examiners are alone in the room with a test subject, his or her behavior greatly influences the results of the exam.

"It's a very serious factor when someone is being accused of a crime," Lee said. "See, I don't care about the deceptive person. I'm looking for the innocent person. I'm their advocate. I'm totally unbiased and neutral when that person comes walking in. But as soon as I make that assessment that there's no deception indicated, I immediately become their advocate."

The forensic psychophysiologist has several tasks in performing a polygraph exam:

  • Setting up the polygraph and preparing the subject being tested
  • Asking questions
  • Profiling the test subject
  • Analyzing and evaluating test data

How the question is presented can greatly affect the results of a polygraph exam. There are several variables that an FP has to take into consideration, such as cultural and religious beliefs. Some topics may, by their mere mention, cause a specific reaction in the test subject that could be misconstrued as deceptive behavior. The design of the question affects the way the person processes the information and how he or she responds.

There are approximately 3,500 polygraph examiners in the United States, 2,000 of which belong to a professional organization, according to Dr. Frank Horvath, a Michigan State University professor of criminal justice and a member of the American Polygraph Association.

Who Uses Polygraphs?
Polygraphs are limited in their use in the private sector, but they are frequently used by the U.S. government. Here are some entities and occasions that may call for the use of a polygraph:
Horvath is concerned about the credentials and qualifications of many polygraph examiners in the United States who do not belong to some sort of professional organization. Laws regarding polygraph licensing vary from state to state, and there is no government or private entity that controls polygraph licensing. Horvath also feels that training of polygraph examiners is inadequate.

"I just do not think the field is at the state where we would say that any polygraph examiner is the equal of all other polygraph examiners. That's just not so," Horvath said. "We have a number of standardization problems in terms of examiner qualifications that concern me enormously. You could buy a polygraph [instrument] tomorrow and come to Michigan and you wouldn't be able to practice here because we have a rigorous licensing law, but you could move down to Ohio and open a business tomorrow."

Today, some polygraph examiners take classes and work an internship in order to become an accredited examiner with national associations. Some states also require examiners to be trained. There are many schools around the United States that have been set up to train people to conduct polygraph exams. One of these schools is the Axciton International Academy, which was started by Lee. The school is accredited by the American Polygraph Association and certified by the American Association of Police Polygraphists.

Here are the steps that students at the Axciton Academy must complete before becoming licensed forensic pyschophysiologists:

  • Prior to enrolling in the school, students must possess a baccalaureate degree or have five years of investigative experience and an associates degree.
  • Students must attend and pass a 10-week intensive course. Curriculum includes psychology, physiology, ethics, history, question construction, psychological analysis of speech, chart analysis and test-data analysis.
  • Students must enter an internship program and conduct a minimum of 25 exams for actual cases. These exams are faculty reviewed. This internship can take anywhere from eight months to one year.

Following the completion of these requirements, the student becomes a polygrapher and may obtain a license in his or her state if that state requires one. There is no standardized test that all polygraph examiners must pass in order to practice.

Going on the Box
Undergoing a lie detector test can be an intimidating experience that can challenge the nerves of even the most stoic person. You are sitting there with wires and tubes attached to and wrapped around your body. Even if you have nothing to hide, you could be afraid that the metal-box instrument sitting next to you will say otherwise. Fittingly, undergoing the uncomfortable experience of a polygraph test is often referred to as "going on the box."


Mouse-over the wire colors to see where they lead.

A polygraph exam is a long process that can be divided up into several stages. Here's how a typical exam might work:

  • Pretest - This consists of an interview between the examiner and examinee, where the two individuals get to learn about each other. This may last about one hour. At this point, the examiner gets the examinee's side of the story concerning the events under investigation. While the subject is sitting there answering questions, the examiner also profiles the examinee. The examiner wants to see how the subject responds to questions and processes information.

  • Design questions - The examiner designs questions that are specific to the issue under investigation and reviews these questions with the subject.

  • In-test - The actual exam is given. The examiner asks 10 or 11 questions, only three of four of which are relevant to the issue or crime being investigated. The other questions are control questions. A control question is a very general question, such as "Have you ever stolen anything in your life?" -- a type of question that is so broad that almost no one can honestly respond with a "no." If the person answers "no," the examiner can get an idea of the reaction that the examinee demonstrates when being deceptive.

  • Post-test - The examiner analyzes the data of physiological responses and makes a determination regarding whether the person has been deceptive. If there are significant fluctuations that show up in the results, this may signal that the subject has been deceptive, especially if the person displayed similar responses to a question that was asked repeatedly.

There are times when a polygraph examiner misinterprets a person's reaction to a particular question. The human factor of a polygraph exam and the subjective nature of the test are two reasons why polygraph exam results are seldom admissible in court. Here are the two ways that a response can be misinterpreted:

  • False positive - The response of a truthful person is determined to be deceptive.
  • False negative - The response of a deceptive person is determined to be truthful.
"If we look at laboratory-based studies, false-positive errors occur somewhat more often than false-negative errors," Horvath said.

Critics of polygraph exams say that even more false-positive errors occur in real-world scenarios, which biases the system against the truthful person. These errors are likely to occur if the examiner has not prepared the examinee properly or if the examiner misreads the data following an exam.