Participants were police officers from 2 small city police departments, with 50 officers involved from 1 department and 30 from the other department. Their length of service as a police officer at the time the MMPI-2 was administered averaged 3 months. Measures of aggressive behavior were obtained from a comprehensive performance evaluation complete by each officer's supervisor after the officer had completed 1 year of service. The study looked for any significant correlations between each officer's score on each of the four MMPI-2 scales and each of the six measures of aggression from the performance evaluations. Analysis of the data on the 80 officers found no significant correlations between any of the MMPI-2 scales and any of the supervisor ratings. Thus, there is no evidence that the four MMPI-2 scales can be used to predict overt aggressiveness in police officers; however, it is possible that a combination of scales, perhaps combined in a weighted regression equation, would increase the potential utility of the MMPI-2 for the prediction of aggression. Another conclusion of the study was that it may not be possible to generalize from one jurisdiction to another when attempting to predict police officer performance from psychological test scores. A test or combination of tests that might have good predictive validity in one jurisdiction may not be useful in another jurisdiction, even though the two departments and their officers appear to be similar, as was the case in this study. 23 references