Lie Detector Test: 4 Factors that Makes it a Great Interrogation Tool

Interrogating a person is difficult. There’s always a possibility that a person will lie. This, of course, obstructs the cross-questioning process and could confuse the interrogators. But thanks to a polygraph which measures and records the physiological indices, it’s easier to know whether a person is telling or a lie or the truth.

A polygraph tests make use of special machines to record the responses to certain questions and is programmed to reveal the evasive and dishonest answers. With an increase in heart rate, this signifies that the person is telling a lie. While the results aren’t exactly accurate, a lie detector test has significantly been a helpful tool, especially in uncovering the truth.

Here are some reasons why it helps:

Detects Dishonesty

Some employees are very dishonest towards their employers. This affects the trust and relationship in a business setting. A polygraph test can help expose the dishonest staffs who are trying to cause harm to a business. While it isn’t exactly conclusive, it could prompt a person to tell the honest stories and situations.


Keep Everyone Honest

Should the use of the polygraph is stated as part of the company’s rules, for example, this stops the temptation or dishonest attitude among the employees. They would be reminded that they would be subjected to lie detector test, so they would try their best to be more inclined to honesty. While such kind of test may affect one’s morale, it can somehow help him or her to stay true and sincere with everything, regardless of the consequences.

Pre-test and Post-test Interview

A lie detector test can pick up whether an applicant is lying to the employer or not. This helps some employers to find out whether the individuals are being dishonest or lying. Under the pressure that a polygraph provides, it can definitely test the candidate’s moral and deters him or her to state lies and false ideas.


Although it’s not completely effective (as the accuracy ranges from 75-95%) it’s still a smart way of knowing a person’s motives and behaviors, especially when put under pressure. When specific questions are targeted, people who undergo this test usually state the truth because they know that they can’t easily manipulate the results and their physiological indices.

As you can see here, there are dozens of good reasons to use a polygraph test. But take note that it has its drawbacks as well. Some people criticize its use because they think that it can’t help on knowing the truth. Still, a lot of companies and organizations highly recognized its importance.