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Neighborhood – Boyle et al. (2010)

Study Reference:

Boyle, D. J., Lanterman, J. L., Pascarella, J. E., & Cheng, C.-C. (2010). The impact of Newark’s Operation Ceasefire on trauma center gunshot wound admissions. Justice Research and Policy, 12(2), 105–123.

Location in the Matrix; Methodological Rigor; Outcome:

Neighborhoods; Focused; Reactive; Moderately Rigorous; No evidence of effect

What police practice or strategy was examined?

This study evaluated the effects of Operation Ceasefire in targeted areas of Newark, New Jersey on gunshot wound admissions to the local trauma hospital. A gunshot wound surveillance system was created at the trauma center to collect data on non-self-inflicted gunshot wound victims between January 1, 2004 and December 31, 2006. Law enforcement teams then investigated the shootings that occurred in targeted locations, and parole officers made home visits to parolees who resided near any shootings that occurred during the intervention time period. The purpose of the home visits was to remind individuals about the consequences of gun violence the the purpose of the intervention. The Ceasefire intervention also included public education regarding the unacceptability and consequences of gun violence, community mobilization to build support for the initiativeyouth outreach, faith-based leader involvement, and criminal justice participation.

How was the intervention evaluated?

Targeted areas for the intervention were determined by police conducting hot spot analysis of gun violence in Newark. Three interrupted time series analyses were used to evaluate the effect of the intervention on gunshot wound admissions to the local trauma  center. A comparison zone was matched to the Ceasefire areas based on a range of criteria that included gunshot wound rates per week, population, number of block groups, and demographic factors. A buffer zone of block groups between the intervention and comparison groups was also created to address any potential intervention work crossing over the targeted zones An additional comparison zone was created to serve as a control for city-wide trends. Treatment and comparison zones were compared before and after the intervention. The pre-intervention period was 71 weeks, whereas the post-intervention was 85 weeks.

What were the key findings?

There was a small decrease in rates of gunshot wounds in the treatment zone, but it was not statistically significant. Additionally, in the matched comparison zone, gunshot wound rates varied throughout the study period, which resulted in a minor decrease in post-treatment gunshot wounds. Moreover, the city-wide comparison zone had consistent rates of gunshot wounds throughout the study period, indicating that the intervention did not result in a change in rates of gunshot wounds within the target area

What were the implications for law enforcement?

Results indicate that Operation Ceasefire in Newark, New Jersey was ineffective and did not result in reducing gun violence as measured by gunshot wound admissions to the local trauma hospital. However, the authors note that they did not study minor gunshot-related injuries that did not require treatment at a trauma hospital or gun-related homicides.

Where can I find more information about this intervention, similar types of intervention, or related studies?