Testing procedure of the polygraph examination

Abstract

There are several methods to examine the testimony, and the same applies to the instrumental methods establishing the truth. The legislator shall only allow the use of the appropriate methods and instruments seeking the truth. In Hungary the most common method for the instrumental examination of the testimony is the polygraph, which provides relevant information for a criminal case. It is conducted with the involvement of an advisor and allows the advisor to conclude, from the physiological changes, generated by the denials of the person being tested, whether the denial was trustworthy, i.e., whether the answer to the question asked by the advisor was deceiving. The polygraph is used by the Hungarian law enforcement authorities since the end of the 70s, after the technical and methodological foundations were created. During the first few years of the use of the polygraph most of the concerns were raised regarding the scientific nature of the examination. The main reason for that was that in the 60s it was regarded as a “capitalist pseudoscience”, it was believed that the application of the polygraph prejudices the fundamental principles of the criminal procedure. These days there have been doubts about the validity of the polygraph, and this makes the biggest dispute on this instrument. The goal of this study is to review the operation of the polygraph. The study presents the course of the examination and reviews the questioning techniques (the concealed information tests and the control questions technique) and presents these through a concrete case.