NCJ Number
80532
Journal
Psychophysiology Volume: 15 Issue: 4 Dated: (July 1978) Pages: 344-359
Date Published
1978
Length
16 pages
Annotation
Control-question (CQ) and guilty-knowledge (GK) techniques for the detection of deception were studied in a mock theft context.
Abstract
Subjects from the local community received $5 for participation, and both guilty and innocent subjects were motivated with a $10 bonus for a truthful outcome on the polygraph examination. They were instructed to deny the theft when they were erxamined by experimenters who were blind with respect to their guilt or innocence. Eight physiological channels were recorded. Blind numerical field evaluations with an inconclusive zone produced 94% and 83% correct decisions for two different types of CQ tests and 89% correct decisions for GK tests. Control questions were more effective than guilt-complex questions, and exclusive control questions were more effective than nonexclusive control questions. Behavioral observations were relatively ineffective in differentiating guilty and innocent subjects. Quantitative analyses of the CQ and GK data revealed significant discrimination between guilty and innocent subjects with a variety of electrodermal and cardiovascular measures. The results support the conclusion that certain techniques and physiological measures can be very useful for the detection of deception in a laboratory mock-crime context. DESCRIPTORS: Detection of deception, Lie detection, Polygraph tests, Control-question technique, Guilty-knowledge technique, Skin conductance, Skin potential, Heart rate, Blood pressure, Vasomotor response. (Author abstract)