These three issues involve the accuracy with which response style under highly stressful conditions can be assessed, the generalizability of response style across situations, and the reliability and validity of third-party observations of behavior. A case description involving a man charged with murder and sexual battery, who was initially believed to be incompetent to stand trial, is the basis for this discussion. After several months it became apparent that this man had no history of prior admissions to psychiatric facilities, that antipsychotic medication had little discernable effect in altering his suspiciousness and reported delusions about the legal system, and that although he was suspicious and uncooperative with professional staff who were evaluating his competency, he acted differently with other staff and patients. To help evaluate his trial competency, a checklist was devised consisting of twenty behavioral descriptions of every symtom he had reported to any examiner or hospital staff member. Selected direct-care staff were then asked to rate him as having displayed any of the behaviors during their 8-hour shift. The results of these ratings were used as testimony to support the conclusion that he was competent to stand trial. The judge was receptive to the idea of this form of testimony, but wanted to know how this data should be interpreted. The three issues raised by his question lack a sufficiently solid empirical base to provide an answer. 17 references.