NCJ Number
240253
Journal
Polygraph Volume: 41 Issue: 2 Dated: 2012 Pages: 77-126
Date Published
2012
Length
50 pages
Annotation
This study examined the reliability and validity of physiological criteria developed by the Department of Defense Polygraph Institute and used by Federal examiners to evaluate polygraph charts for probable-lie examination.
Abstract
This study had three primary objectives: 1) assess the reliability and validity of physiological criteria used by the Department of Defense Polygraph Institute (DoDPI) to indicate deception; 2) determine which of the criteria Federal examiners used to evaluate polygraph charts for probable-lie examination; and 3) propose a method for combining DoDPI criteria in order to maximize the accuracy of polygraph decisions. Regarding the 3 objectives, the study found that for the physiological criteria, 12 of the 25 were diagnostic of deception in a sample of confirmed field cases. Of the 12, 3 had low reliability, 1 was an artifact of question position, 3 did not generalize to an independent sample of laboratory cases, 2 did not generalize to an independent sample of field cases, leaving only 3 criteria that were valid and reliable indicators of deception across 3 independent samples of cases. The study also found that Federal examiners based their numerical evaluations of electordermal, cardiovascular, and respiration responses primarily on response amplitude, increase in baseline, and decrease in line length, respectively. Based on these findings, a set of recommendations is presented for use in polygraph testing and evaluation of the results. Tables, figures, references, and appendixes