The research focused on the Structured Interview of Reported Symptoms (SIRS) and the Georgia Court Competency Test-Mississippi State Hospital (GCCT-MSH). The sample consisted of 115 males in the San Diego, Calif., area. Thirty simulators were compared on both instruments with 23 incompetent defendants, 25 competent defendants, 30 offender controls, and seven suspected malingerers. Results revealed that the simulators and suspected malingerers scored significantly higher on all the SIRS primary scales and significantly lower on the GCCT-MSH than the three comparison groups. The SIRS had an overall hit rate of 97.8 percent using three or more primary scales as the criterion for malingering. The strategies of deception used by the simulators who evaded detection on the SIRS included imitating a person, imitating a disorder, and endorsing questions related to emotional problems. On the whole, simulators were quite unsophisticated in their faking strategies. Findings indicate that clinicians can confidently use the SIRS to assist with malingering determinations, although cutoff scores may need to be adjusted as a function of the population of defendants evaluated. More research including suspected malingerers is also needed. Tables and 22 references (Author abstract modified)