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Polygraph Testimony in Criminal Cases

NCJ Number
Polygraph Volume: 41 Issue: 1 Dated: 2012 Pages: 39-43
Stanley M. Slowik
Date Published
5 pages
In discussing issues related to polygraph testimony in criminal cases, this article focuses on areas relevant to both foundation experts and practitioners: competency, standardization, technique, and examiner bias.
Regarding competency, there are testimonial advantages to being licensed by an independent State licensing agency instead of being certified by the school to which the polygrapher paid tuition; however, the principal issue in competency relates to the requirements of certification compared to licensing. In situations where there are significant differences between the two measures of competency, examiners should always become qualified under the more stringent standard. More problematic, however, are the internship requirements of the various training programs, an internship that involves a real-life subject is more desirable than one that involves role-playing with other polygraph students. Regarding the standardization of training and practices, in addition to standardizing polygraph school curriculum and membership requirements, the American Polygraph Association (APA) has also established Standards of Practice that manage to include different instructional methods and poly graph techniques, all of which are variants of the standard Reid Control or Comparison Question technique. Regarding technique, examiners should focus on the strength of what techniques have in common rather than the technical differences. Although there is a major differences between Relevant/Irrelevant and Control/Comparison question techniques that directly influence validity and reliability, the difference between inclusive and exclusive formulation pales in comparison. Testimony should focus on examiner competency and procedures and principles that adhere to practices that can be proven to be valid and reliable, not just in common use. Regarding examiner bias toward the defense or prosecution, the easiest and most objective way to demonstrate a lack of bias toward an employer or requester is to provide evidence of the testifying examiner's services to both the defense and the prosecution at various times. 2 references


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