How Accurate Are The Polygraph Tests?

Polygraph tests are also popular as lie detector tests and are conducted by an investigator to reveal the actual facts of an incident. They are generally carried out by the government of the respected country. A polygraph test is carried out with the help of lie-detecting equipment connected to a person with numerous wires. The lie detector tests have a limit of a maximum of ten questions to be asked by the questioner. It is assumed to be conducted to the suspect at the time when is least expects it. But at the same time, he is provided a trial session of the test to make him understand the tricks and methods to conduct the lie detection test.

Benefits of polygraph tests: Certain benefits of lie detecting test are followed by a government can cause these things to happen.

  1. Show the true face: A polygraph test is known to disclose the true and real facts related to the incident that has happened. It shows the real faces of every suspect while conducted by the government officials.

  2. Helps in government: The lie detector test is known to assist the government authorities at a very wide level. It is advised to the suspect to speak only truth while in the monitoring of legal authorities.

  3. Reveal the truth: Polygraph tests are known to be conducted for the revelation of certain facts. Lie detector tests have become a popular method or way of disclosing the information regarding the occurred event in a very short period. 

  4. Eliminate the suspects: By asking questions from every suspect of a criminal offense, there remains very few to ask questions from. It gradually lessens the number of suspects in a case by reaching to the real criminal of the evil doing.

Does the polygraph test enforced by law? 

Commonly, a polygraph test is managed by government officials to reveal the real faces of their suspects. It enables them to find the real criminal by applying the elimination method. It is generally a very tricky procedure to follow, only conducted if someone is aware of the tips to follow while following the polygraph test. It is an art to carry out tests like these, as they demand huge knowledge of each hormone released by our brain while answering different types of questions.

How does a lie detector test work? 

Most of the in times, a lie detection test is conducted for revealing the authentic self of each suspect available in the suspect room. A lie detector test mainly consists of wires connected to the nervous system of the body of the suspect. The wires are linked to a strip of moving blank paper that displays the heart rate, blood pressure, pulse rate, breath rate, etc. of the connected individual. If the person is getting fluctuations in blood pressure and other systems of his body, then the known to be lying about the asked question. But this polygraph test does not always seem to provide accurate answers to the questions because an honest person can also become anxious due to some reasons other than lying about the happened events.

What is the role of sweat in a polygraph test? 

Electrodes are connected to the fingers and nervous system of the human in a polygraph test. Various types of hormones are released while sitting on the chair linked to the lying detection process. Any change in the sweat of the suspect, along with the blood pressure, heart rate, etc. is noted down accurately that determines the final consequences of the suspect being a criminal or not. It is said that when a person is lying, more sweat will be excreted through his sweat glands. Hence, the recording on the moving paper linked to the sweat glands displays the amount of sweat released by the glands. It is known to be extremely useful while detecting the liars among the crowd of suspects.

How much time a polygraph test takes? 

Usually, a polygraph test is required to take a minimum time of 1 hour and a maximum of two or three hours. But it also depends on the number of questions to be asked from each of the suspects. Generally, ten to eleven questions are permitted by the government to ask from every suspect. That, too, varies from country to country and offense to offense.

What is the accuracy percentage of a polygraph test? 

The accuracy of a lie detector test is recorded to be 90% world-widely according to some statistics. But survey reports on behalf of critics’ displays a percentage of 70% to be true. The rest of the opposed population says that a dishonest and fake person can be so confident in answering to the replies of the asked questions, and an honest and true person might be anxious in disclosing the facts. Hence, we cannot conclude for a criminal solely based on the results of a polygraph test. 

About Oblena

Janica Oblena is the writer of ‘Midnight Secrets’. She is a graduate of Harvard University with a degree in Journalism. She is currently the senior editor of
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