Effects of polygraph chart interpreter experience on psychophysiological detection of deception

Fifty actual criminal polygraph records of examinations conducted according to standard control question techniques, were selected. The selection was random with the exception that half of the records were of innocent examinees verified by the confession of another person and half of guilty examinees verified by their own confession. The records were evaluated by a group of five experienced polygraph examiners (three years or more) and a group of five trainees in the seventh and eighth months of their internship program. Both groups used the semi-objective numerical scoring technique described by Barland and Raskin (1975). Results indicated that experienced scorers exhibited a significantly better detection rate than trainees when they scored the respiration channel, while no significant differences between the two groups were obtained when scored both the GSR and cardiovascular tracings. Results were discussed with relation to previous findings and in reference to theoretical requirements for a scientific, credible study for real-life polygraphy.