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Just Enough Police Presence: Reducing Crime and Disorderly Behavior by Optimizing Patrol Time in Crime Hot Spots

NCJ Number
Justice Quarterly Volume: 12 Issue: 4 Dated: (December 1995) Pages: 649-672
Date Published
24 pages
Using observational data collected as part of a 1-year preventive patrol study in Minneapolis, this study employed survival models to test hypotheses about the effects of specific instances of police patrol presence at high-crime locations on the time until the next occurrence of criminal or disorderly behavior at these locations.
Data were obtained from the Minneapolis Preventive Patrol Experiment which examined the effects of preventive patrol at 100 hot spots between December 1988 and November 1989. A hot spot was defined as a cluster of addresses which produced 20 or more hard crime calls and 20 or more soft crime calls over a 1-year period. The study focused on the effects of police patrol presence, not on any particular style of policing or set of police activities. Continuous time, parametric event history models were used to determine whether longer police patrol presence created residual deterrence in the form of longer survival times without disorders. Results showed police patrol stops had to reach a threshold dosage of about 10 minutes in order to generate significantly longer survival times without disorders, i.e., greater residual deterrence, than that generated by driving through a hot spot. The optimum length for police patrol stops appeared to be 11 to 15 minutes. After that point, continued police presence brought diminishing returns. Theoretical and policy implications of the findings are discussed. Supplemental descriptive statistics and survival data are appended. 48 references, 14 footnotes, 4 tables, and 2 figures

Date Published: January 1, 1995