Mazerolle, Soole and Rombouts have conducted a systematic review of research on “Street Level Drug Enforcement” for the Campbell Collaboration (PDF).

They find the following tactics are promising:

1. Geographically targeted problem-oriented policing interventions, involving partnerships between police and municipal department, community groups, or place managers (businesses, residential managers), tend to be more effective at disrupting street-level drug markets than policing efforts that involve partnerships but are spread across a community. (NOTE: We also suggest coordinating efforts to the timing of drug markets)

2. Simply increasing police presence or intervention (e.g. arrests) at drug hotspots is less effective than (1) focusing on forging productive partnerships with others, (2) targeting drug hotspots rather than spreading intervention efforts across neighborhoods, and (3) making efforts to alter the underlying conditions that exist in places that may contribute to street-level drug market problems.

3. Some recent research indicates that patrol cars with license plate cameras on them seem to reduce drug calls in crime hot spots.

NOTE: Problem solving approaches in this review also include nuisance abatement, closing down problem locations, and improving the quality of life in these areas by contacting appropriate municipal agencies regarding code violations.