Право/5. Уголовное право и криминология

Неверова А.В., Багенц Д.С.

Южно-российский государственный университет экономики и сервиса

The use of polygraph in the detection and investigation of crimes

To understand the use of polygraph in the modern world we need to come to the origins of the disclosure of lies. It is also necessary to understand that those who tell a lie deliberately and those who are not still have one thing in common: the moment when a person tells a lie a series of psycho-physiological changes take place in the human body: the intensity of sweating, pulse rate, respiration rate and the tone of the vessels. We can see quite obvious dependence of the psycho-physiological state of a person on the situation which threatens to expose him. Various tests on the suspects were based on this dependency. It was intended to register such changes in his/her condition so that it would permit to come to a conclusion of his/her guilt or perjury. Consequently, we can conclude that the modern polygraph is a set of precise medical devices continuously and simultaneously recording the dynamics of psychological reactions of a questioned person where each physiological parameter is recorded in a particular order.

The practical results of the use of polygraph abroad show that for example in Latvia and Belarus the psycho-physiological testing can serve as evidence in criminal and civil proceedings including those in their Supreme Court. But we must take into account the fact that the data obtained from a polygraph is probable, i.e. we have 85.95% of the later established facts and such results come to be a real impediment to the administration of justice in several U.S. states. According to the legislation the testimony of polygraph can be taken into account in trial only if the defense and the prosecution come to such an agreement. It is also worth noting that the use of polygraph in the judicial and investigative practice allows the persons concerned to prove their innocence and also makes it possible in specific situations to find evidence to support the prosecution. Now we can go to the subject of psycho-physiological testing where the method in question will be thoroughly investigated.

This psycho-physiological research suggests correct questions. They must not be polysemantic, hard to understand. They must match his/her intellectual level, must not be offensive, have no pronounced emotional color, in other words, the preparatory work takes sometimes much more time if compared with the examination itself. Two methods are used when polygraph test is concerned. They are direct and indirect methods. The direct method implies that the subject is asked three groups of questions in sequence: relevant (critical) - relating directly to the investigation of the circumstances of the crime; irrelevant (neutral) - not related to the case and asked to reduce the emotional tension or to shade the reaction to critical issues; control - not related to the investigated crime but having some "condemnatory" content. It is assumed that the accusation which is contained in the control questions must not exceed the force of the accusation contained in the relevant questions. It is established that a person who is not privy to a cause reacts more strongly to control questions than to relevant ones since they contain dangerous for him/her "condemnatory" information.

In order to distinguish reactions to neutral and target questions a certain technique of asking questions was selected. The so-called neutral-target method was developed by the polygraph founder Maxtan in 1917. It has long been the standard for validity check. The essence of the neutral target method is the following: a number of questions are asked: some are neutral, irrelevant to the case; some are meaningful when we want to find out the person’s attitude to a particular case. In different versions they can go in mixed order ,for example, one question is significant, then a neutral one or can go block by block, for example, 5 neutral questions are followed by a block of 5 critical ones, then again five neutral questions and 5 critical ones. Everything is recorded so that the experts watch people’s reaction to the group of neutral questions. Then they do the same with the questions from the critical group. After that they compare answers to certain blocks of questions. The expert conducting a psycho-physiological examination must not answer the questions about the answers which turned out to be a lie because it goes beyond the expert’s competence. The task of the expert is to monitor and interpret the reaction to verbal information. It is up to the investigator in charge to make a conclusion whether the involved information was true or false. He can do it only by comparing and analyzing the results of psycho-physiological examination and all the collected materials of the criminal case. Of course, such results of expert studies can optimize the investigation considerably.

The culmination of this problem is the criminal procedure aspect. First of all the question about the forms, conditions and limits of the use of polygraph in criminal trials must be preceded by a comprehensive analysis and followed by a discussion of the results by scientific elite and qualified experts. The specific nature of home proceedings and the mentality of the population must be taken into account, too. Such research is carried out quite successfully in the Home Office and the Federal Security Service of the Russian Federation. The results of their work are assumed to be the basis of the instruction “On the procedure of polygraph testing during the interrogation of the citizens” adopted by the Prosecutor General's Office and registered on December 28, 1994 at the Ministry of Justice of the Russian Federation as well as by the order of the Minister for Internal Affairs of the Russian Federation dated from September 12, 1995 № 353 "On the adoption of the polygraph in the internal affairs practice."

We would also like to note the contradictory nature of data that is known in home and international practice when criminals escape punishment by simulating sudden mental disorders thus cheating the whole committee of eminent scientists and psychiatrists but no one suggests banning forensic expertise. The probability of deception on the part of the subject is comparable though. Thus, the device which for decades has been considered immoral by the liars and scoundrels can be used nowadays by not only the power structures of different countries but also by various commercial organizations and sometimes even by families. However, the lack of legal regulations for a polygraph testing holds back its use as evidence in the detection and investigation of crimes. That’s why at present this method serves exclusively in order to obtain orienting information.