Effective Writing

Topic: The use of polygraph tests by law enforcement

Research Question: How accurate are polygraphs as tools for lie detection?

Thesis Statement

Polygraphs are unreliable and are not foolproof, therefore they should not be used by law enforcement as means for determining whether or not a person is telling the truth as well as be admitted as evidence in the court of law.

McCarthy, S. (2000, March 2). Passing the polygraph. Salon. Retrieved August 20, 2006, from http://archive.salon.com/health/feature/2000/03/02/ lie_detection/index.html

The article reveals that professional criminals are the ones most adept at deceiving polygraph devices (more commonly known as lie detectors) and how one can easily beat it with a little knowledge and training. Lie detectors are widely used by various parties especially in the United States. While many people believe in its reliability, evidence suggests that its accuracy and validity is dubious. This article supports this conjecture and shows that it is possible to “Beat the Man”.

Through the author’s research, she discovered that there are countless literature on how one can beat the lie detector–plenty of scientific as well as anecdotal examples were used to illustrate this point. In one study, it was revealed that the person’s responses to polygraphs can be “trained”, meaning one can easily pass the test with enough skill and experience. The author cites many instances from the book “A Tremor in the Blood” by David Lyken that reveal various circumvention techniques.

Also according to Lyken, test results often correspond to the person’s state of mind–if one believes he is innocent, that will be the likely result, regardless of whether or not that person committed a crime. This article would be very useful in supplying evidence for arguing my point on how polygraphs can be inaccurate and untrustworthy–using it as evidence on any case can have innocent people convicted and help the guilty ones get away scot-free–therefore it should not be used as a means for determining truth from lie, as well as be admitted as valid evidence in court.

Neil, B. (2005, January 25). Your Number Is Up When Trying to Lie. Evening Chronicle, p A22.

The article reports how polygraph or lie detector tests can be accurate gauges of a person’s honesty and discusses how this tool can be used for monitoring a convicted sex offender’s risk to the public. The author took a lie detector test herself to illustrate that lies could not escape the polygraph. However, this attempt falls short in proving the test’s infallibility, since it does not necessarily mean that all people who “lie” gets caught.

Shay Addison, the polygraph tester whom the author interviewed herself admitted that accuracy is not absolute–the degree of error, according to her, is about 10%. According to the author, the polygraph test helps in uncovering truth about certain aspects of a crime that an offender may be in denial about. It purportedly allows them “know the way offenders are thinking.” However, she does not cite any reliable source or research supporting polygraph use.

Post-interview responses in the polygraph test are discussed, in which many would confess what they have been holding back (although they would usually already be a fair idea of what is being held back by the offender)—this illustrates that other factors (such as pressure) leading to a perpetrator’s self-confession are the ones that help reveal the truth, rather the polygraph test per se. The article is mainly an exploration into the feasibility of the polygraph’s use as a compulsory test before releasing pedophiles, however it’s conjecture that polygraphs are decisive tools for discovering the truth is fallible and inaccurate