The Psychology of Criminal Conduct

There are other, more recent examples of the polygraph being used, such as the insurance group Admiral's statement that a form of lie detector helped cut car theft claims by 25%. They said that after using a type of voice analyser known as 'Digilog' where a caller's voice is recorded and analysed for irregular stress levels, a quarter of car theft claims were withdrawn. Admiral stressed that it did not mean all the withdrawn claims had been fraudulent, saying some may have been dropped as a result of stolen cars being found. They have since extended the trial period of the use of this technology indefinitely (BBC, 2003).

The confidence in the worthiness of the product is shown in Digilog's company slogan: 'Wherever there is a requirement to test truthfulness, we have a solution for you. ' (http://www. digilog. org/about. htm) Each of these examples suggests that the UK is taking an open-minded view on the reliability of the polygraph. It appears that the most useful role for the polygraph in this country would be of a criminal nature. Whether it is used to prevent crime or as an aid to detection, the polygraph offers a method of identifying deceit, even if it remains a relatively untested and somewhat crude design.

However, the opinion of the validity of the polygraph is somewhat different in America. It has been in use a lot longer there, thus a variety of pro and anti-polygraph groups have been able to take shape. It follows that the more a product is tested, the more one is able to see its flaws, and this is what has happened in the US. Unfortunately for the government its flaws involved breaches of national security. In the case of Wen Ho Lee, a nuclear scientist employed by the Department of Energy in 1998, the polygraph was used to detect whether Lee had given away some of America's top nuclear secrets in a Chinese espionage scandal.

The initial report was clear: Lee had honestly answered no when asked various questions regarding the passing on of nuclear information. However, the FBI announced several weeks later that in fact Lee had failed the polygraph test. It was uncertain for even more weeks after that what the correct result was, leading the public to form their own beliefs about the reliability of the polygraph, as well as the integrity of the FBI. Eventually it was discovered that the initial result was actually the correct one and Lee was cleared of all charges (CBS, 2000).

This is a prime example of the government abusing the polygraph in order to provide a solution, resulting in giving the machine an unreliable name. As the interest and popularity of the polygraph grew in the US it was deemed necessary to pass the Employment Polygraph Protection Act of 1988. This act provides that a business cannot require a pre-employment polygraph and cannot subject current employees to polygraph exams. A business can request an exam, but cannot force anyone to undergo a test. If an employee refuses a suggested exam, the business is not allowed to discipline or discharge that employee based on his or her refusal.

However, all federal government agencies exempted themselves from this act, allowing them to carry out polygraphs at their discretion. This would lead one to believe that they are a reliable and acceptable means of investigation: if the most trustworthy jobs in the country rely on the polygraph to find the best person for the job, then surely it has to be a fool-proof piece of equipment. However, this is not the belief of members of www. antipolygraph. org. George Maschke, co-founder of the website organisation against the use of polygraphs claims he was falsely accused of being a spy when he applied for employment with the FBI in 1995.

He says his belief that the polygraph was a science-based technology, albeit admittedly imperfect, was one of naivety and in fact, the polygraph has never been shown in scientific research to be capable of distinguishing truth from deception (Maschke, 2001). There are numerous other people who back up this belief, including former senior scientific expert on polygraphs for the FBI, Dr Drew Richardson: "Polygraph screening is completely without any theoretical foundation and has absolutely no validity… the diagnostic value of this type of testing is no more than that of astrology or tea-leaf reading.

" (Richardson, 2001, as cited in Maschke, 2001) The other main argument is that the emotions and responses measured by the polygraph can be as a result of the actual taking of the test, as well as feelings of nervousness, embarrassment, fear, guilt or anger (Williams, 2003). Doug Williams was a detective sergeant with the Oklahoma City Police Department and ran the polygraph section of the Internal Affairs Division for over six years. He resigned from his position and chose to spend his time training (and earning money from) people to beat the polygraph.

It is apparent that in aspects of the media there are many organisations wanting to inform the world of ways to beat the polygraph. It seems like America has gone polygraph paranoid. Society has been forced to become suspicious of this machine because of the way it has been portrayed by both the government and the media. An act of federal government has had to be passed in order to protect the interests of the public: this in itself suggests that there are still ethical and scientific concerns about the use of the lie-detector.

The biggest opponent to polygraph admission in court is the US federal government, which happens to be the largest consumer of polygraph exams in the United States. This clearly implies beyond reasonable doubt that the polygraph is not being used for its intended purpose. In the UK, the validity of the machine is confirmed in few procedures, criminal or otherwise. In its current state it is evident that the polygraph holds minimal value and authority in this country due to the way it has been represented both here and in America.

The polygraph will remain an issue of controversy as long as it continues to have a role of any sort in society, especially as there are barely any standards or laws regarding its employment, and it does not appear in the majority of significant cases to have been a reliable tool to determine deceit in police investigations.


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