A Case Study of the Validity of the Arther Examination Procedures in a Criminal Case with DNA Confirmation

We report a case study of the Arthur Examination Procedures (AEP). The validity of the AEP was examined in the case records from a high profile actual innocence case. Through legal discovery at a retrial and subsequent civil action, materials from 27 AEP polygraph examinations were obtained. Of the 27 examinations, 21 resulted in conclusive opinions. Nine of the examinees were shown to be actually innocent by DNA exclusion. Of those nine examinations 4 were shown to be false positive errors. Statistical analyses show that the outcome pattern from these data closely match those of the only published study of the validity of the AEP. The analyses also show that it is almost impossible that the data from this case were produced by a highly accurate polygraph technique. Examiners who use the AEP should consider retraining in one of the validated versions of the comparison question test.