Optimizing Patrol Time in Crime Hot Spots: Replicating the “Koper Curve”

• In Event: Optimizing Patrol Time in Crime Hot Spots: Revisiting the “Koper Curve” Strategy After 30 Years - Sponsored by the Division of Policing

Abstract

This study seeks to replicate and extend research on the “Koper Curve” strategy of hot spots patrol, which emphasizes regular but unpredictable stops of 11-15 minutes at hot spot street blocks and intersections. This strategy, which is based on Koper’s 1995 analysis of data from the Minneapolis Preventive Patrol Experiment, is used by many agencies worldwide and has proven effective in several field tests. However, Koper’s original finding on optimal patrol length has not been replicated in other settings. Using methods similar to those used by Koper, we analyze data on hot spot patrols and crime incident reports to precisely measure the occurrence of crime and disorder at micro hot spots relative to the comings and goings of police. Specifically, we evaluate initial and residual deterrence effects (measured as the time to the next crime or disorder event) from proactive patrol visits of different lengths to high-risk locations. The study updates and extends Koper’s research by examining longer patrols and follow-up periods than those used in his original study, and by using data on more than 150,000 hot spot patrols across ten localities.

Authors

• Lester Wollman, SoundThinking

• Christopher Koper, George Mason University

• Simen Oestmo, SoundThinking