Managing Director, Forensic Polygraph Services; 1st Vice President, ASIS (local chapter) and Treasurer, Jamaica Society for Industrial Security.

It is said that we humans are slaves of our emotions and no one knows this better than a polygraph examiner. More over, the effectiveness of Forensic Psycho-physiology lies in the polygraph examiner’s knowledge of the causes and effects of emotions and ability to structure a test that will contain certain emotions while allowing others to release onto a carefully prepared stimuli scientifically arranged to elicit responses that will distinguish truth from deception.

Ones emotions consist of intensified feelings caused by interaction between the mind and the body regarding a situation resulting in physiological changes within the body to cope with the situation. The pattern and the degree of physiological changes may vary according to the intensity of the feelings and the type of situation. When these feelings are strong the accompanying physiological changes are extensive.

Under such conditions the adrenal gland begins to release adrenaline into the bloodstream stimulating the heart into greater activity, thereby increasing circulation. The circulatory system begins to redistribute the blood supply, taking it away from the stomach and the intestines where it is not needed at that moment and sending it to the large muscle groups such as the arms and legs where it is more needed. The liver begins pumping glycogen into the blood stream providing a quick source of extra energy. Breathing rate increases and the spleen begins dispatching large numbers of additional red corpuscles into the bloodstream thus enabling the lungs to extract more oxygen in the air; the body is in a state of full emergency.

This sequence of events is known as the Flight or Flight Syndrome and is controlled by the para-sympathetic and sympathetic divisions of the autonomic nervous systems. During a polygraph test, it is fear, the fear of detection and the fear of the consequences if the subject is detected that causes the sympathetic system to activate. Therefore a sense of guilt is not an essential element to activate the sympathetic system.

It is not the act of lying that necessarily activates the sympathetic system but rather the reason for the act. It is for this reason why experiments conducted in laboratory conditions for the purpose of validating the effectiveness and reliability of polygraph examinations, although successful, do not reflect the high degree of response, level of accuracy and effectiveness experienced by forensic psycho-physiologists in the field because it is most difficult if not impossible to stimulate the fear of detection in a laboratory situation as compared to an actual live situation where an examinee’s well-being is truly being threatened by some form of punishment if the discovery of their lie becomes known.

Recognizing that the underlying basis of Forensic Psycho-physiology is the emotion of fear, the polygraph examiner must also appreciate that anger can also induces sympathetic responses. It is therefore necessary that adequate safeguards be adopted to preclude the element or state of anger from entering or interfering with the polygraph examination. Hence, the pre-test interview. It is against this background, that the examinee is asked how they feel about being tested and given an outlet to vent their anger and release any anxieties.

To address this variable, certain rules are adopted by forensic psycho-physiologists which dictate that no accusatory approach should ever be used in a pre-test interview and interviewing techniques that convey the impression that the polygraph examiner does not believe in the subject’s innocence are considered taboo. During the interview phase, the examiner must therefore establish rapport with the subject and evaluate the their physiological and psychological suitability to undergo the test. Provided the polygraph examiner conducts a properly executed pre-test interview, the polygraph technique is considered 95% accurate for single-issue tests.

Since June 1999 I have administered over 1500 polygraph tests and investigated over 600 cases. A recent conducted survey of 700 persons revealed that approximately 2/3 of my subjects were males, 1/3 females, that 62% of the males tested failed as opposed to 48% of the females, that 75% of all the specific issue cases involved employee theft, that 60% of those who were interviewed following a failed test confessed and that less than 5% of all subjects interviewed refused to be tested. One of the reasons for the relatively low refusal rate is the fact that the technique is still novel and the average Jamaican believes they can beat it and there lies its success.

When one considers that 4 out of 5 small businesses fail because of employee theft, that 2 out of three 3 employees have stolen from their company at least once and ½ of those at least twice, that males steal more than females, that supervisors steal 4 times the value of their line staff, that managers steal more than supervisors, that directors steal more than managers and that the average fraud scheme lasts 18 months before being detected, it is useful to know that the medical science has through the use of Forensic Psycho-physiology provided an effective crime-fighting solution.