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. Case Report903 the examinee. Electrodermal activity is considered to be the most sensitive and critical parameter among three channels used in polygraph examination [5]. It is governed by the eccrine gland, which is a sweat producing gland controlled by the sympathetic nervous system [6].There are a variety of activity sensors utilized during polygraph examination which include seat pads, foot rest pads, and arm activity sensors. These activity sensors are used to monitor the movements with which an examinee tries to distort the physiological data during a polygraph in a respective area, e.g. seat, foot and arms.The Forensic Assessment Interview Technique (FAINT)[7] is used as a pre-assessment tool. It was devised by Gordon and Fleisher [7] and has been translated into Urdu by Shujaat and Rizvi [8]. In FAINT, two parallel assessments are developed e.g. verbal and nonverbal assessment.FAINT has two researched and objective scoring systems, namely a three-point scoring system and weighted scoring system, which are employed for more accurate pre-test assessment.Polygraph examination begins with an acquaintance or number test. The examinee is given one to six numbers and instructed to choose one number by circling the number.He is asked to answer questions by circling the consecutive numbers and also instructed to say "no" on a selected number. The examinee is informed regarding the rational of the number test.After the acquaintance test, all the test questions are properly discussed and reviewed with the examinee and he is instructed to answer all the questions with yes or no. It is important that the examinee understands the test questions and their related responses. It is further communicated to the examinee that lying to any test question will lead to

The emergence of “truth machines”?: Artificial intelligence approaches to lie detection

“…I largely draw from US and UK examples in this article, but development of AI-enhanced lie detection technologies is growing in HR worldwide (Ayoub, 2018;Bergers, 2018). Alder (2009) writes of the "obsession" of the US with lie detection devices, but it is a passion increasingly shared with other nations, including China, which originally resisted the proliferation of lie detection technology (Zhang, 2011), and Germany (Fischer, 2020).…”