NCJ Number
152749
Journal
Polygraph Volume: 23 Issue: 3 Dated: (1994) Pages: 195-218
Date Published
1994
Length
24 pages
Annotation
The validity of an expanded issue, control question polygraph technique that is commonly used in criminal investigations was tested with simulations of thief, accomplice, confidant, and innocent crime roles.
Abstract
Respondents included 96 individuals who were paid for their participation in the polygraph study. Subjects performed their assigned roles by following written and recorded instructions without personal coaching. Each subject participated in two sessions about 1 to 2 weeks apart. Crime role simulations were conducted in the first session, while polygraph examinations were conducted in the second session. Field numerical scores and objective measures discriminated between guilty and innocent groups. Excluding inconclusives (guilty-18.1 percent/innocent- 20.8 percent), decisions based on total numerical scores were 84.7 percent correct for the guilty group and 94.7 percent correct for the innocent group. Relatively weaker but significant discrimination was observed between the thief group and the other guilty groups. No significant discrimination was found between accomplice and confidant groups. Skin conductance, respiration, heart rate, and cardiograph measures contributed most strongly to discrimination. Implications of the findings for field practice are discussed, and suggestions for further research on the expanded issue polygraph technique are offered. 29 references and 4 tables