The polygraph as a lie detection tool: history, function, and controversy

Polygraph

There has always been a search for a way in the social order regarding the degree of truthfulness or dishonesty in an individual. History reveals that there has been almost a universal constant endeavor to uncover the falsehood and know the truth. The Ancient Chinese, Arabs and Indians are known to have used methods from torture to duel fight for obtaining the truth and distinguish innocent and guilty (White Jr., 2001, p. 483).

This quest of differentiating the liar and the honest still goes on today. One of the modern-day methods to distinguish truth from fraud is the use of the polygraph (lie detector). The polygraph is both favored and criticized by the modern man. It is defended on the basis of its success as innumerable criminals have confessed and numerous spies and terrorists have been uncovered when tested through the polygraph. Moreover, its capability in revealing the employee theft and saving millions of dollars has also made polygraph a dependable instrument. On the other hand, polygraph is considered a quackery and trick by its critics who claim it to be erratic, illogical and variable. They regard it as an unreliable tool that has branded countless innocent persons as guilty (White Jr., 2001, p. 483).

What is a Polygraph?

A polygraph is a sensitive and receptive electronic examining device. It uses ink writing pens for marking out diverse types of physiological responses on a moving chart paper. Modern polygraphs are convenient and transportable that can fit inside an attache case. It monitors and examines those physiological reactions that are run by the autonomic nervous system. Autonomic is that branch of the nervous system that is susceptible to an individual's emotional states. Three types of autonomic responses i.e. palmar sweating, blood pressure & pulse rate and respiratory activity are usually measured using a polygraph. The signals that are received from these autonomic responses are recorded while different types of questions are asked to the suspected individual. Thus, polygraph examiners scrutinize the record obtained on the resulting paper to determine whether the person is truthful or not (Brewer & Wilson, 1995, p. 156).

Brief History

In order to detect lie, oafish and horrible methods were used by the civilizations that existed as early as 300 B.C. The hot iron method which required the suspected individual to lick a hot iron was used by the Bedouins of Arabia. The person was regarded as truthful is his or her tongue did not get burned. Similarly, the rice powder method was developed by the ancient Chinese. In this method, the person was asked to place rice powder in the mouth. he/she was considered as honest if the rice powder came out moist. The belief that governed these practices was that those people who lie have a dryer mouth and less saliva. Primitive people who detected lies using such method believed that those who are not nervous and tell the truth have moist mouths with more saliva (Lewis & Cuppari, 2009).

In the 18th century, the adverse method of burning was used. The accused was to stick his or her hand into a pot of boiling water. He or she was considered as lying if the hand was burned. The individual was considered to be lying. In the same way, a test was conducted in which red hot stones were used to find out the reality. The person was considered untruthful if his/her feet burned (Lewis & Cuppari, 2009).

To end with, it was the Italian criminologist, physician, and anthropologist, Cesare Lombrosso who in 1881 created the first contemporary lie detection device called Lombrosso's Glove. Using this instrument, Lombrosso attempted to measure changes in the blood pressure of the accused. He recorded those changes on a graph/chart. Later, another lie detection technology was introduced during the World War I by William M. Marston who used it to inquire the prisoners of war. This technology turned out to be a popular one in criminal investigation. However, the credit of the creation of the first genuine and authentic polygraph goes to John Larson and Leonarde Keele as it could measure and record blood pressure, respiration, and pulse. At the present time, the polygraph training is widely available throughout USA and other countries where this detector is used during the examination of criminals (Lewis & Cuppari, 2009).

Criticism

Despite its usefulness, the use of polygraph is not encouraged by the scientific community due to a lack of evidence that could support this device's dependability and soundness. Though the polygraph is being used by law enforcing agencies, counterintelligence departments, private sectors etc., there has been much debate over its testing reliability. Most of the critics of the polygraph regard it as a 'junk science' that has no logical or methodical foundation. However, the fact that polygraph utility has helped police and criminal justice system cannot be denied. It is not essential that polygraph will always produce erred results. It has aided the police in solving various difficult cases and seeking the truth. Polygraph testing has helped law enforcement investigators to acquire and get hold of the absolute facts. This aid by the lie detecting device has brought innumerable guilty persons to justice. If the validity or reliability of a polygraph is kept at one side, it would be obvious that the testing done by it offers the investigators an important tool to employ in interviews. This could really be helpful in terms of obtaining additional important information (Warner, 2005).

Conclusion

The polygraph is the most renowned device that has been created for identifying cheating and determining truth. In the long line of techniques, this device has become the most appreciated way to identify criminals. The investigators related to the law enforcement and intelligence communities value this method highly during the investigation and interrogation processes. In the absence of direct evidence, the polygraph testing has helped tremendously in discovering spies and saboteurs. Its supporters believably claim that the polygraph do has a basis in modern science. They believe so because the polygraph depends on measures of physiological processes. Despite constant criticism, the polygraph has been able to help the law enforcers find out the wanted criminals, spies and informants (Faigman, Fienberg & Stern, 2003).

The world today has become a hub of terrorists and criminals who are all ready to devastate the society and create anarchy. Thus, it is really important for the law enforcement professionals to make use of all the techniques and strategies that are available in order to protect their respective communities. If the investigators are deprived of a valuable tool like polygraph that could help them to solve crimes or put a stop to expected catastrophes, the consequences could be severe and far-reaching (Warner, 2005).