Since the 1960's Great Britain has shifted its emphasis from a medical model to a crime control model in dealing with illegal drugs. Thus, new powers have been provided for the investigation of drug law offenses, and the boundaries of criminal justice intervention have been widened. These changes resulted from the perceived gravity of the drug problem, its growth and location in the youth protest and counterculture movements of the late 1960's and early 1970's, the alleged failure of treatment, and the logic of the penal argument that had always been the basis of British policy. However, the changed policies have resulted in the diversion of law enforcement resources, threats to civil liberties, the encouragement of organized crime, a focus on marijuana, and a heightened risk of civil unrest among minority groups and youth. Case studies from one court, footnotes, appended tables, and 18 references.