The polygraph, also known as a lie detector test, is a method of lie detection that has been used for many years. But how accurate is it, really?
And should you take one if you’re ever asked to do so?
How do lie detector tests work?
Lie detectors, or polygraph tests, measure an individual’s physiological responses to questions posed by an examiner to determine whether they are telling the truth. Generally speaking, when individuals lie, their body responds in specific ways that can be detected and measured.
During the test, the examinee is hooked up to a series of sensors to monitor specific physiological changes, including pulse rate, blood pressure and perspiration rate. The examiner then quizzes the examinee with predetermined questions to identify features that correspond with lying behavior. On the positive side, polygraph tests can provide insight into an individual, uncovering previously unknown information.
However, it’s important to note that polygraph tests don’t actually prove if someone is telling a lie. They only measure involuntary bodily reactions that might indicate deception. But, several factors can compromise the outcome of the test, including:
- Level of examiner’s experience
- Test environment
- Mental illness
Furthermore, some people have learned how to manipulate the test’s output.
It’s important to note that polygraph tests are generally not admissible as evidence in court due to their unreliability and validity. If you are ever in a situation where you are asked to take a polygraph test, it’s best to consider all your legal options before making a decision.