Evidence-Based Policing Matrix
Neighborhood – Sherman et al. (1995)
Sherman, L. W., Shaw, J. W., & Rogan, D. P. (1995). The Kansas City gun experiment: Research in brief. Washington, DC: National Institute of Justice.
Sherman, LW & Rogan, DP. (1995). Effects of gun seizures on gun violence: “Hot spots” patrol in Kansas City. Justice Quarterly 12:673-693.
Shaw, J.W. (1995.) Community Policing Against Guns: Public Opinion of the Kansas City Gun Experiment. Justice Quarterly 12(4):695–710.
Location in the Matrix; Methodological Rigor; Outcome:
Neighborhoods, Focused, Proactive; Moderately Rigorous; Effective
What police practice or strategy was examined?
This study examined the impact of directed patrols focused on gun crime hot spots. The intervention was conducted in one police beat (an eight-by-ten block area) in Kansas City, MO that had very high levels of gun violence. For 29 weeks from July 7, 1992 to January 27, 1993, police patrols were increased in locations identified by computer analysis as having large amounts of gun crime in the target area. Assigned officers focused exclusively on gun detection through proactive, directed patrol and were not required to answer calls for service.
How was the intervention evaluated?
The researchers examined project implementation measures, such as gun recoveries, traffic stops, field interviews, and arrests. They also analyzed trends in gun and non-gun crime in the target area and compared them to trends in a similar comparison area that did not receive the patrols. Pre and post-intervention surveys of the target and comparison beats were also conducted to measure citizen perceptions of the program.
What were the key findings?
A comparison of the 29 weeks before the program began and the 29 weeks while the program was active revealed a 65 percent increase in guns seized and a 49 percent reduction in gun crime in the target area. There was no increase in gun seizures or reduction in gun crime in the comparison area. Traffic stops were the most productive means of finding illegal guns, producing an average of 1 gun discovered for every 28 stops. Gun crimes did not increase significantly in any of the surrounding seven patrol beats, demonstrating that there was not a displacement effect. The results of the surveys indicated that although residents of both areas perceived their neighborhood as having changed for the better seven months after the program, this change was greater in the target area.
What were the implications for law enforcement?
The authors suggest that directed patrols can be effective in reducing gun crime when focused on gun detection in gun crime hot spots. The directed patrols were about three times more cost-effective in removing guns from the street than were routine police activities. Additionally, the results of the survey indicate that the patrol program did not increase community tensions; most residents supported the intervention, and it appeared to have positive effects on citizen perceptions.
Where can I find more information about this intervention, similar types of intervention, or related studies?
- All studies in the Matrix on neighborhoods
- Braga, Papachristos, and Hureau’s systematic review on hot spots policing effects on crime
- CrimeSolutions.gov Practice Profile: Hot Spots Policing
- Information about hot spots policing
- CEBCP Special Lectures and Research Clips: Putting hot spots research into practice- Chris Koper
- The POP center problem guide on gun crime