NCJ Number
63899
Date Published
1979
Length
102 pages
Annotation
THE EFFECTS OF DETAILED INFORMATION AND PRACTICE ON THE CONTROL QUESTION (CQ) TECHNIQUE FOR PHYSIOLOGICAL DETECTION OF DECEPTION (PDD) WERE STUDIED IN A MOCK THEFT SITUATION.
Abstract
A MOCK THEFT WAS COMMITTED BY 36 SUBJECTS, WHILE ANOTHER 36 SUBJECTS WERE SIMPLY INFORMED ABOUT THE THEFT. ALL SUBJECTS WERE INSTRUCTED TO DENY HAVING COMMITTED THE THEFT WHEN THEY WERE ADMINISTERED A CQ POLYGRAPH EXAMINATION WHICH MEASURED SKIN CONDUCTANCE, BLOOD PRESSURE, RESPIRATION, AND DIGITAL VASOMOTOR ACTIVITY. ALL SUBJECTS WERE OFFERED A $10 BONUS FOR PRODUCING AN INNOCENT OUTCOME ON THE POLYGRAPH TEST. PRIOR TO THE TEST, GUILTY AND INNOCENT SUBJECTS RECEIVED EITHER (1) NO INFORMATION (STD), OR (2) DETAILED INFORMATION ABOUT THE CQ TEST AND SUGGESTIONS ABOUT METHODS TO APPEAR INNOCENT (INFO), OR (3) THE DETAILED INFORMATION AND SUGGESTIONS PLUS TWO PRACTICE POLYGRAPH TESTS (INFO+PRAC). EACH SUBJECT WAS THEN GIVEN A CQ POLYGRAPH TEST BY AN EXAMINER WHO WAS BLIND REGARDING THE SUBJECT'S GUILT OR INNOCENCE OR THE TREATMENT ADMINISTERED. THE POLYGRAPH CHARTS WERE NUMERICALLY EVALUATED BLINDLY BY A THIRD EXPERIMENTER WHOSE SCORES PROVIDED THE BASIS FOR DECISIONS WAS 95 PERCENT FOR THE STD GROUP, 95 PERCENT OF THE INFO GROUP, AND 71 PERCENT OF THE INFO+PRAC GROUP. ANALYSES SHOWED SIGNIFICANT DISCRIMINATION BETWEEN GUILTY AND INNOCENT SUBJECTS, INCLUDING MEASURES OF SKIN CONDUCTANCE, RESPIRATION, BLOOD PRESSURE, AND VASOMOTOR ACTIVITY. RESULTS INDICATED A HIGH DEGREE OF EFFECTIVENESS OF THE CQ TECHNIQUE EVEN WHEN SUBJECTS WERE GIVEN DETAILED INFORMATION ABOUT THE TESTS AND WAYS TO DEFEAT IT. HOWEVER, THE COMBINATION OF INFORMATION AND PRACTICE SIGNIFICANTLY WEAKENED THE EFFECTIVENESS OF THE CQ TECHNIQUE WITH INNOCENT SUBJECTS. TABLES, GRAPHS, AND REFERENCES ARE INCLUDED. APPENDIXES CONTAIN PRELIMINARY INSTRUCTIONS, A NEWSPAPER ADVERTISEMENT, POLYGRAPH INFORMATION, AND A QUESTIONNAIRE. (AUTHOR ABSTRACT MODIFIED--PRG)