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What is a polygraph examination?

A polygraph or lie detector examination might best be described as a truth verifica­tion examination.  While all eminently qualified polygraph experts must always remain neutral and not be swayed by someone’s appearance, age, gender or personality, each examiner must be doing everything within their power to influence the person taking the test to have a fa­vourable result.  Anyone and everyone can pass the examination simply by being completely truthful about the issue being examined and do so during the pre-test polygraph interview.  Irrespective of what the person taking the test may have done, by being truthful during the pre-test interview, it guarantees their successes in passing the examination.  For example, if someone was being tested for a theft at his or her place of business, and they discuss this with the examiner, one of the relevant test questions might be, “Other than what you discussed with me before this test, have you stolen any more of the missing money or product?”  It is our experience that since a wider margin of those taking the polygraph test have favourable truthful responses, it might be best to refer to the examination as a “Truth Detector” as opposed to ‘Lie Detector.”  The word polygraph is from the Latin, “Many Writings.”  A modern day polygraph instrument evaluates multiple physiological responses, thus, “Poly,” as in “Many” writings, graph.

What does the polygraph procedure involve?

Once a person or company has scheduled an examination, a block of time is allocated to properly conduct a pre-test interview, the examination itself, a possible post test interview and occasionally, the preparation of a typed report which outlines the issue under consideration, the relevant test questions, and the opinion of the expert who administered the examination.  The test itself is traditionally the component of the entire polygraph examination process that takes the least amount of time.  The purpose of the pre-test interview is to garner as much information as necessary to prepare the test ques­tions.  It also allows the examining expert the opportunity to explain the instrument itself, and to an extent, what physiology is actually being recorded.  Multiple issue tests should never be conducted.  For example, a standard series of test questions may contain many questions about a singular is­sue….such as theft, arson, fidelity or child molestation.  Yet, it would never include both issues during the same examination.  Typically, polygraph experts would ask a client to explain the general nature of the test and specific information to formulate the test questions.  Clients that require testing of mul­tiple issues should know that to accomplish this type of testing, it also requires different testing sessions, generally on different days of testing.  No compound questions should be allowed and conjunctions are never allowed.  For example, your expert would never ask a question such as “Did you rob and kill John Doe?”  The reason for not asking such a question is that if deception to that question were noted on the test tracings, the examiner would not know whether the person taking the test robbed, or killed John Doe, or did both.  We encourage all clients to allow us to assist you in identifying the most critical issues in formulating the test question format.

The examination does not cause pain.  There can be some slight discomfort with the pressure in the blood pressure cuff, but since the actual chart time for each series of questions is typically un­der three minutes, there is usually a slight numbness or tingling as opposed to a painful expe­rience.  All test questions are reviewed with each person being tested.  Surprise questions are never allowed and we urge anyone who has agreed to participate in this testing technique to ter­minate the test should any unrevealed questions be asked during the test.  Always remember, you control whether you take this test and you may feel free to discontinue it at any time.

Any person that appears to have been drinking alcoholic beverages will be refused for testing.  Any person that appears to be physically unfit for testing because he or she has used drugs, pre­scribed or otherwise will also be rejected if the examining expert feels that they might interrupt the proper interpretation of the examination.  Of course, polygraph experts do not want you to stop taking your medication.  Taking your prescribed medication is important and does not mean that an effective and accurate test is not possible.  In almost all cases, successful completion of the test will be quite possible.  We usually will be able to identify anyone who has taken drugs or narcotics for the sake of getting high, or “low” as the case may be, and your chart tracings will immediately identify whether or not  you are a suitable “subject” for testing.

All persons taking a polygraph/lie detector test will be provided with their test results.