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Polygraphs Are Better Than Lying

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Polygraphs measure bodily functions in order to evaluate whether or not the subject is telling the truth. It combines three readings to achieve results: heart/blood pressure, respiration, and skin conductivity. The heart and blood pressure is measured with a blood pressure cuff around the wrist, respiration is judged using pneumographs around the chest, and skin conductivity is found by electrodes placed on the fingertips. The subject is then asked a series of preliminary questions to set readings and ensure that the equipment is working. Once the polygraph is set up, the interviewer begins one of the two primary types of polygraph tests.
The Control Question Test (CQT) is the more popular of the two. The interviewer will ask both relevant
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The majority of the research regarding polygraphs conclude that while they are better than chance, they simply aren’t anywhere near as precise as many people claim. The primary issue is that polygraphs really measure arousal, not “lies”. There are many different reasons for the subject to be aroused outside of lying, such as anxiety, PTSD, nervousness, confusion, and withdrawal. There is no evidence that physiological reactions exist that are unique to deception. In fact, Dr. Saxe and Israeli psychologist Gershon Ben-Shahar (1999) note that, "it may, in fact, be impossible to conduct a proper validity study." In addition to the questionable scientific foundation of polygraph tests, there are a great many variables that can affect results as well. Tests are done in many different ways, purposes, and procedures, not to mention the influence that examiners, examinees, and situational factors have on the validity of the…show more content…
Aldrich Ames, a Soviet spy who passed the test said that his method was to "Get a good night's sleep, and rest, and go into the test rested and relaxed. Be nice to the polygraph examiner, develop a rapport, and be cooperative and try to maintain your calm." He also stated "There's no special magic....Confidence is what does it. Confidence and a friendly relationship with the examiner...rapport, where you smile and you make him think that you like him." Other countermeasures exist, such as memorizing the questions as they are reviewed by the examiner, then artificially raising your heart rate during the irrelevant questions, and remaining calm for the relevant ones in order to give the illusion of truthfulness.
Aldrich Ames was not an exception either, there have been many other guilty people who have passed the test. Karl Koecher, Ana Belen, Montes, and Leandro Aragoncilla were all spies who successfully tricked the polygraph test. The test also failed to catch Gary Ridgway who became known as the “Green River Killer”. Ridgway was only caught 20 years later from DNA evidence that was
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