How to Know If Your Someone is Lying to You

The word “polygraph” means “many things”. The name refers to selected physiological activities that are collected simultaneously and recorded. The polygraphic instrument simultaneously records changes in physiological processes such as heart rate, blood pressure and breathing.

Today there are two types of polygraph instruments. There is the analog instrument (the type you can see the pens move on graphics paper) and the most advanced computerized instruments. A polygraphic instrument will collect physiological data of at least three systems in the human body. The convoluted rubber tubes placed on the top of the chest and the abdominal area of ​​the candidate will record a respiratory activity.

How to Tell Lies From the Truth

In the pretest phase, the polygraphic examiner will fill out the required documents and speak with the  lie detector test  candidate. During this period, the examiner will discuss and examine the questions to ask, discuss the question tested and familiarize the candidate with the test procedure and the polygraph instrument.

During the graphic collection phase, the examiner will administer the polygraphic examination and collect a certain number of polygraph graphics. Following this, the examiner will analyze the graphics and make an opinion on the veracity of the person passing the test. The opinion rendered will be one of the following elements: no deception indicated (truthful), the deception indicated (not truthful), not conclusive (the examiner is unable to determine veracity or deception), or none Opinion (the exam must have been stopped before completion or an anomaly was noted). In the post-test phase, the examiner will offer the candidate the possibility of explaining the physiological answers in relation to one or more questions asked during the  lie detector test.

Pre-Employment Polygraph | Pre-Screening | Lie Detector Test

Errors in polygraph exams:

  • False positive and false negative
  • Although the polygraphic technique is very precise, errors can occur. Polygraphic errors can be caused by the failure of the examiner to properly prepare the candidate for the examination or by a misinterpretation, the physiological data collected during the polygraphic examination.
  • Errors are generally false positives or false negatives. A false positive occurs when the candidates are truthful and are reported as being misleading. A false negative occurs when the candidate is misleading and reported as truthful.
  • Since it is recognized that any error is harmful, the examiners use a variety of procedures to identify the presence of factors, which can cause false responses and ensure an impartial review of polygraphic recordings. 

Who gets results?

According to various laws on state licenses and the norms and principles of practice of the American Polygraph Association, the results of the polygraph can only be released to authorized persons. Generally, people who can receive test results are the candidate and any person specifically designated in writing by the candidate. Such as the person, the company, the company or the government agency, which requested the examination and others, can be required by legal proceedings.

Eligibility for court

It is largely the general opinion of the public that the results of polygraph  lie detector test  are not authorized in court. The fact is that the results of the polygraphs are eligible in most courts across the country. The Supreme Court has not yet ruled on the issue of eligibility, it was therefore individual jurisdictions to allow or prohibit them.