4 Myths and Facts About Polygraph Tests

Polygraph tests, commonly known as lie detector tests, have long been a vital and instructive tool that can be used in a variety of scenarios.

As soon as a lie detector is mentioned there is a heightened level of fascination about how they work. It is also often the case that the line between myths and facts can be blurred when the topic of conversation is a polygraph test.

Regularly used in various useful contexts, from criminal investigations to employment screenings, several myths have arisen around the technology and its applications.

Here, we dispel four common myths and present the facts about polygraph tests.

Polygraph Tests Can Read Minds

This is probably the most classic myth that persists in relation to how a lie detector works. Let’s dispel this myth with a fact.  Polygraphs measure physiological responses, which is a more scientific and real way to establish whether someone is telling the truth or not.

A polygraph is designed to measure physiological responses such as heart rate, blood pressure, respiratory rate, and skin conductivity, which may indicate stress or nervousness.

The underlying theory is that deceptive answers will provoke a stronger physiological response than truthful ones. However, these responses can also be triggered by anxiety, fear, or various other reasons unrelated to deception. That’s why it requires a trained professional to interpret the responses correctly.

Polygraph Tests Are Infallible

The fact that polygraph tests have been used for so many years is testament to their reliability and insightful abilities. However, polygraph tests are not 100% accurate

Very few systems can claim total accuracy, especially when you are analyzing human responses. Despite their use in certain legal and professional settings, the accuracy of polygraph tests is not absolute.

The American Polygraph Association claims accuracy rates above 90% under controlled conditions, which can be considered a high success rate.

There are various factors, including the skill of the examiner, the quality of the equipment, and the test subject’s psychological state, that can influence the outcomes.

Only Guilty People Fail Polygraph Tests

The bottom line is that innocent people can potentially fail a polygraph test for a variety of valid reasons.

Stress, nervousness, or fear of being disbelieved, regardless of innocence, can trigger physiological responses that may be interpreted as signs of deception, especially if the examiner does not have the right skills and experience.

To a certain extent, the way questions are formulated and interpreted by the examiner can affect the outcome. Polygraph results are generally designed to be an investigative tool to support the evidence gathering process.

All Polygraph Examiners Are Equally Skilled

The assumption that all polygraph examiners possess the same level of skill and professionalism is another myth. Examiner experience and training can vary widely.

The reality is that the experience and qualifications of polygraph examiners can vary widely. Some countries and states have strict licensing requirements and professional standards for polygraph examiners, while others do not. The quality of the examination can significantly influence the results, making it critical for those considering a polygraph test to research and select their examiner carefully.

Polygraph tests can provide valuable insights. As long as you understand the need to use an examiner with the right level of experience and ability to interpret the results you can look forward to an accurate response.