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General Deterrent Effects of Police Patrol in Crime "Hot Spots": A Randomized, Controlled Trial

NCJ Number
Justice Quarterly Volume: 12 Issue: 4 Dated: (December 1995) Pages: 625-648
Date Published
24 pages

Recognizing that many criminologists question the effectiveness of uniformed police patrols in producing measurable crime differences, the authors conducted a 1-year randomized trial in Minneapolis to assess the effect of increases in police patrols at 55 of 110 crime hot spots.


Crime hot spots were operationally defined as small clusters of addresses with frequent crime calls for police service. The final sample consisted of 110 hot spots where crime calls were concentrated between 7:00 pm and 3:00 am. The 110 hot spots were randomly assigned to two groups of 55. The experimental group received twice as much observed police patrol presence as the control group. Outcome measures included crime calls and observed disorders, and the study hypothesized that substantial increases in police patrol in crime hot spots would reduce reported and observed crime. Findings revealed reductions in total crime calls that ranged from 6 to 13 percent. Observed disorders were only half as prevalent in experimental as in control hot spots. The authors conclude substantial increases in police patrol can modestly reduce crime and generate more impressive reductions in disorders at high- crime locations. 39 references, 9 footnotes, 3 tables, and 3 figures

Date Published: January 1, 1995