Does Phencyclidine (PCP) Use Increase Violent Crime?

Abstract

Phencyclidine (PCP) has obtained a notorious reputation for provoking violent behavior. Because of this reputation and a number of methodological weaknesses in PCP-violence studies, the recent research literature on the relationship between PCP use and violent crime was reviewed. Studies were organized according to types of subjects studied (PCP users in treatment; PCP users in the criminal justice system; and PCP users at large in the community). Within each category, studies were evaluated in terms of the logical rigor of their research design and measurement. Of the three categories, investigations involving PCP users in the criminal justice system tended to have fewest problems. However, methodological weaknesses in some studies and contradictory findings in others did not allow one to adequately answer the question of whether PCP use increased violent crime. Unanswered questions and suggested directions for future research in the PCP-violence field are presented.