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Groups – Braga et al. (2014)

Study Reference:

Braga, A. A., Hureau, D. M., & Papachristos, A. V. (2014). Deterring gang-involved gun violence: measuring the impact of Boston’s operation ceasefire on street gang behavior. Journal of Quantitative Criminology, 30(1), 113-139.

See also:

Braga, A.A., Apel, R., & Welsh, B.C. (2013). The spillover effects of focused deterrence on gang violence. Evaluation Review, 37(3-4), 314-342.

Location in the Matrix; Methodological Rigor; Outcome:

Groups; Focused; Highly proactive; Rigorous; Effective

What police practice or strategy was examined?

The study reevaluated Operation Ceasefire, a problem-oriented policing implemented citywide between January 2007 and December 2010 aimed at reducing youth firearm violence in Boston. The program involved a “pulling levers” strategy by reaching out directly to gangs, putting gang members on notice that offenders face certain and serious punishment for gang violence, and “pulling every lever” legally available when violence occurred. Simultaneously, youth workers, probation and parole officers, and other community groups offered meaningful resources and opportunities to help youth escape the gang lifestyle. Nineteen Boston gangs were subjected to such focused deterrence over the course of the project.

How was the intervention evaluated?

Propensity score matching techniques are used to develop matched treatment gangs and comparison gangs that are comparable on nine characteristics including number of shootings committed in the pre-Ceasefire year, gang membership size, and so forth. Gangs that are socially connected to the Ceasefire gangs are excluded from the comparison pool beforehand to avoid contamination. Yearly and quarterly change in gang-involved shootings for treatment and comparison gangs over the 5-year observation period (2006-2010) are compared using non-fatal firearm incident report data.

What were the key findings?

Shootings involving Boston gangs subjected to the Operation Ceasefire treatment were reduced by a statistically significant 31% when compared to shootings involving matched comparison Boston gangs. Supplementary analyses found that the timing of gun violence reduction for treatment gangs followed the application of the Ceasefire treatment.

What were the implications for law enforcement?

The authors suggest that Operation Ceasefire strategy is effective in controlling street gang violence problems. However, the authors caution that the violence reduction estimate is a more conservative estimate compared to the two-thirds reduction in youth homicides reported in the original Ceasefire evaluation in 2001, potentially due to the earlier study’s weaker research design.

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