Determining the points at which group behavior moves from legitimate activity into an unruly mob and finally into a criminal riot is difficult. In addition, labeling behavior as a 'riot' can influence the course of events. Police intervention may extend and intensify a riot. Crowd behavior and decisions regarding police responses to it reflect political and social factors. Use of the criminal justice process to control collective behavior has a long history. However, crowd control often now represents the institutionalization of confrontation between police and the working class use of public space for recreational and political purposes. The use of the criminal justice process to deal with riots is problematic because the fact criminalization focuses on individual behavior, whereas a riot represents collective behavior. Policing a riot involves crowd control, but the result of this policing is the identification of individual offenses and offenders. Thus, using the police and courts to deal with collective behavior involves basic contradictions and is often inappropriate. Notes and 36 references.