While police officers should be well-informed about rules governing their powers and practices, not all rules represent guiding principles of behavior. When rules are internalized, however, they are likely to have more consistent controlling influence. Working rules are internalized by police officers as guiding principles of conduct. Inhibitory rules are not internalized but are taken into account by police officers when deciding how to act. Presentational rules exist to give an acceptable public appearance to the way police work is carried out. The author contends that the Police and Criminal Evidence Act is not based on an accurate picture of the relationship between law and policing practices. He cites as an example police powers to stop and search which are not always based on law. The need for effective regulation of police policies and practices is emphasized, particularly in the context of police powers to stop and search. 14 notes