Human factor is the major challenge that stands on the way of the specialists in the field of criminal law. Sometimes, the clues may be confusing and the only way to solve the case is retrieving the answer from the people involved. This is when deception and lie become the ultimate challenge in the struggle for the truth. To deal with this problem, the science offered the criminalists a marvelous solution – the lie detector, the device that recognizes the lie. But is it really that good and accurate? The work of the polygraph is based on reading the basic involuntary reactions of our bodies to certain questions and situations. Such reactions usually involve changes in heart rate, blood pressure, sweating, and pulse rate (Kleiner, 2002). Quite simple, is it not? For this reason, many people think that there must be some ways to trick the lie detector. Indeed, there were cases when the polygraph delivered the results that were later proved wrong. This paper intends to examine the topic of lie detectors in more detail to figure out whether they are efficient instrument for the detection of deception and if they can be tricked somehow.
There are certain legal challenges in using such instrumentation for the detection of deception as the polygraph and the voice stress program. First of all, the voice stress program is not proven to be reliable by the competent researchers and specialists. For this reason, it cannot be used to screen applicants, for example, since the Equal Employment Opportunity Commission has stringent rules requiring any test used in hiring decisions be scientifically validated (United States, 2002). On the other hand, polygraph is the only lie detection technique that has been approved by independent scientific reliability and validity studies. It is the only lie detection technique directly used by federal government agencies for investigatory purposes, and it is used by more state and local law enforcement agencies than any other technique available. However, polygraph can never be used covertly.
In chapter 7 of his book The Polygraph and Lie Detection, Steven Feinberg discusses the issues raised by using polygraph evidence for making practical decisions, particularly in security screening processes, including the issue of combining polygraph evidence with other sources of information. The author indicates that negative polygraph results on individuals or on populations of federal employees should not be taken as justification for relaxing other security precautions. Several justifications are given for reducing the use of polygraph screening, including the “severe morale problems” that polygraph screening has caused, the lack of acceptance of polygraph screening among the DOE laboratory employees, and the lack of “conclusive evidence for the effectiveness of polygraphs as a screening technique”.
In chapters 12-14 of the book The Lie Detector, the History of an American Obsession by Ken Alder, once can find short stories about investigators working with the lie detector. Mr. Keeler, a young researcher assigned to make technical improvements to the machine, saw it as a crime-fighting tool and promoted it accordingly, constantly volunteering to solve celebrated crimes and basking in the ensuing publicity (Grimes, 2007). As the lie detector captured the public imagination, in banks, factories and departments of government the magic machine carved out a role for itself, offering a clean technological solution to messy human problems. A landmark legal decision in 1923 barred lie-detector tests from being introduced as evidence in the courtroom.
References
Alder, K. (2007). The lie detectors: The history of an American obsession. New York: Free Press.
Fienberg, S. E. (2003). The polygraph and lie detection. Washington, DC: National Academies Press.
Grimes, W. (2007). “The Tangled Web of the Truth Machine”. The New York Times. Retrieved from http://www.nytimes.com/2007/03/02/books/02book.html?_r=0
Kleiner, M. (2002). Handbook of polygraph testing. San Diego, Calif: Academic Press.
United States. (2002). U.S. Equal Employment Opportunity Commission handbook for administrative judges. Washington, D.C.: U.S. Equal Employment Opportunity Commission.
