Lie detector tests are often portrayed in film and television as a method by which truth is extracted from the person taking the witness stand. In these shows, the wires attached to the perpetrator’s body is also connected to a machine, which etches a couple of lines onto a piece of paper. A qualified professional would then determine whether the person is telling the truth or not. To the untrained individual, it all seems like a figment of one’s imagination. However, there is a science to it.
Psychology reveals that a person experiences physiological responses that varies depending on the situation he’s in. Experts believed that when a person tells a lie, he experiences internal changes, which is often unseen by the naked eye. Thus, they have devised a method which is able to determine whether a person is experiencing these internal responses. They were able to come up with the Polygraph Test.
The polygraph test, famously known as the lie detector test, is a means by which a person’s physiological indicators are measured and recorded to determine whether he is speaking of the truth. Simple detectors measure a person’s blood pressure and heart rate simultaneously, while the more complicated models are capable of recording blood pressure, pulse, respiration, and skin conductivity all at once.
Recent studies reveal that the accuracy rate of these polygraph tests range from 75% to 95%. Since what is being tested is something internal, this number is already quite impressive.
Usage and Benefits
With the growing recognition and acceptance of lie detector test results, people are slowly making a shift towards utilizing it for their benefit. Among its many uses, the most common is in aid of social research work.
Lie detectors are often used by social scientists in determining how a person’s nervousness can affect the way he answers questions. Although not exactly used to determine the truth of a person’s statement, the device would be capable of determining and recording changes in his physiological indices. Thus, this social experiment is often done through conducting pre-interview and post-interview tests.
Some companies also benefit from using polygraph tests. If it is expressly stipulated in the company’s anti-theft policy that they are authorized to conduct polygraph tests to single out possible culprits, then it may significantly reduce the employees’ temptation to commit such felony. And even if it has been committed, the idea itself of undergoing such an exam would already generate enough pressure to nudge the perpetrator into admitting to the crime. Additionally, this is also a great way of screening potential personnel.
Another known use for these lie detectors is for assessing the truth as to the statement of suspects and witnesses in non-judicial settings. These are often employed by prosecutors, police officers, or lawyers in order to guide them with their cases. Law enforcement officers also benefit from these tests, since it helps them monitor post-conviction offenders who are currently out on probation. It must be noted, however, that lie detector tests are not widely recognized as a means of ascertaining the guilt of the accused. In order to convict, there must be guilt beyond reasonable doubt, and that standard entails the presentation of reliable pieces of evidence to solve the puzzle.
And finally, portable lie detector toys are also gaining popularity as a party favorite. These toys were created with the same algorithm as real lie detectors, and would have the liar face certain consequences – often in the form of a slight electric shock. Nonetheless, it must be noted that the results of the toy is not guaranteed to be 100% accurate.
Although widely accepted, polygraph tests are not considered as an accurate source of truth. Different people have different reactions to various situations, so a person’s set of physiological indices may not be the same as another’s. This reduces the device’s reliability, which is also the reason why it is not yet an accepted mode of ascertaining guilt.
Polygraph tests can also be a waste of time. There is a chance that the machine may end up misreading the result and result in falsely accusing a person. And although the accused can prove his innocence, the authorities have already wasted so much time in trying to convict him while the culprit still runs free. They would have to conduct the procedure all over again. Nonetheless, it must be noted that instances like this doesn’t always happen.
These tests can also be quite expensive. Aside from the price of a lie detector itself, hiring a qualified professional to interpret the results can drill a hole in one’s pocket.
Lie detector tests generally offer credible results, especially when it comes to assessing the person’s honesty in answering revealing statements. It can easily benefit companies and the authorities during investigations. Additionally, it can also be a source of entertainment during social occasions. With all these benefits, minor lapses of these lie detectors are certainly outweighed.