How Does The Polygraph Test Work?
At the outset, the examiner obtains a complete background information on the case. The polygraph test or examination proper consists of 3 phases. During the first phase, the pre-test phase, the examiner discusses with the subject the test issue , thoroughly reviews all of the test questions that will be asked during the test,and assesses the subject’s emotional and physiological suitability to undergo the polygraph test. The testing phase consists of a series of tests where the subject’s physiological responses are recorded as the subject answers a set of questions reviewed earlier. The polygraph theory, is based on psychophysiological principle, is that when the subject hears a question which he or she intends to lie, the brain interpretes and triggers automatic and uncontrollable phsiological changes captured by the polygraph. During the post-test phase, the examiner reviews all test data obtained and interprets the polygraph charts, from which the examiner will reach one of 3 conclu
