NCJ Number
122239
Journal
Polygraph Volume: 18 Issue: 1 Dated: (1989) Pages: 15-23
Date Published
1989
Length
10 pages
Annotation
A study to determine the usefulness of the movement chair, which detects movements from transducers in the seat and back rest of the subject's chair, and to determine whether the pneumatic movement channel should be considered necessary for all polygraph instruments is reported.
Abstract
Polygraph examination records (N = 600 sets) were examined using the Stoelting Multigraphic 22715 instrument and grouped by evidence of movement. If there was evidence of movement, a correlation between the movement of the subject and the type of question then being asked was reviewed. There was some concern whether the movement chair reflected all movements and whether a movement could be reflected in channels other than the movement chair. Analysis of polygrams categorized as either truthful or deceptive indicated that movements should be viewed as indications of deception, but that lack of movements should not be viewed as indications of truthfulness. Furthermore, it was concluded that the pneumatic movement channel does not significantly aid in the detection of movement. Graphs.