The Polygraph and Lie Detection: A Case Study

Abstract

There are many cases in which physical evidence is missing. In such instances, a polygraph is a useful technique to determine the examinee’s truthfulness or deception. A polygraph is an instrument that monitors the changes inside the body. The present study was conducted to determine the truthfulness of the victim and suspects in a hand chopping case. In the present study, integrated zone comparison technique (IZCT) and forensic assessment interview (FAINT) were used to test the suspects and the victim. Computerized ASIT Algorithm and weighted scoring systems were used in IZCT and FAINT, respectively. Two suspects and one victim were referred for polygraph examination. Electro-dermal activity sensors were placed on the victim’s forehead as he did not have arms, and a cardio cuff was placed on his left leg. During the initial interview, the victim alleged that his hands were put forcibly into a machine. All the suspects were also tested, and the victim was found to be deceptive. He later confessed that his hands were not put forcibly into machine. After testing, it was found that all the suspects were truthful.

Keywords

• forensic sciences
• integrated zone comparison technique (izct)
• forensic assessment interview technique (faint)
• asit polysuite algorithm
• weighted scoring