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Part 7 - The Polygraph Examination

Deputy Bob Cooley

The polygraph or lie detector examination is right up there in anxiety levels as the pre-employment interview. All kinds of questions roll around in the applicant’s head as to what the polygraph examiner might ask. When I took the very first polygraph I felt the same way. I had visions of the examiner going all the way back deep into my childhood to drag to the light transgressions committed when I was ten years old. I’m not going to sit here and tell you I was an angel, but I can truthfully say I wasn’t “Damien” from the “Omen” series of movies either.

The polygraph is an electro-mechanical device also known as a lie detector used to determine whether an examinee is truthfully answering questions. It simultaneously measures and records certain physiological changes in the human body, which it is believed, are involuntarily caused by an examinee’s conscious attempt to deceive an interrogator (Black’s Law Dictionary 1990).

The examination is conducted by a trained and certified operator who has a list of questions, which will be asked during the test. He or she will ask the questions beforehand and record in writing your responses to those questions. From that question pool the examiner will ask you the questions both he or she believes are important to the examination as well as questions required by the agency. Usually the operator/examiner will take an applicant through the test three times in order to establish a baseline for the applicants physiological state and then twice more for the purpose of detecting deception.

First, please do not take any medication unless your doctor prescribes it. Cold medications, cough syrup and other over the counter remedies can have an adverse affect on your polygraph results. Every polygraph examiner I have ever dealt with has asked as one of the first questions whether or not I had taken any form of medication or alcohol. So unless you have a bad cold or the flu don’t take anything! If you are sick enough to take medication you might want to consider asking for a change in date for the test.

Second, come for the test dressed in comfortable cloths, but again as I pointed out in the pre-employment interview section wear clothing that will reflect favorably upon you.

Third, listen carefully to the questions from the examiner before you answer. This applies to the pre-test and the actual examinations. You don’t want any misunderstanding to occur between you and the examiner by misinterpreting a question.

Fourth, relax you will not be hit by a jolt of electricity caused by the machine so try to stay as calm as possible during the examination. The examiner will give you a chance to take a break between tests so sit back take a deep breath.

Continue To Part 8: The Physical Examination

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