ANALYSIS OF POLYGRAPHIC DATA

To evaluate the feasibility of adapting rapid processing techniques to the present art of polygraph interpretation, it was necessary to evaluate and study the various factors affecting the processes of interpretation of polygraphic data. Two types of decision situations are characteristic of lie detection investigations the dependent judgment case in which the examiner, after comparing all records, selects the guilty individual and possibly accomplices from among a group of suspects known to include the culprits and, the independent judgment case, in which a decision of innocence or guilt is made independently for each suspect on the basis of his record alone. In the latter situation the suspects are usually apprehended one at a time and at irregular intervals. The accuracy of measured and rated physiological response systems used in lie detection was studied. The measured characteristics of three physiological response systems were found to be as accurate as the ratings of the lie detector operators in discriminating between culprit, collaborator, and innocent suspect.