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Groups – Circo et al. (2021)

Study Reference:

Circo, G. M., Krupa, J. M., McGarrell, E., & De Biasi, A. (2021). Focused deterrence and program fidelity: Evaluating the impact of Detroit Ceasefire. Justice Evaluation Journal, 4(1), 112-130.

Location in the Matrix; Methodological Rigor; Outcome:

Groups; Focused; Highly Proactive; Moderately Rigorous; No evidence of an effect

What police practice or strategy was examined?

This study evaluated the Detroit Ceasefire program, a focused-deterrence initiative that used street-level intelligence to identify high-risk individuals for gun-related violence. Weekly meetings were held with personnel from multiple organizations to identify incidents involving gangs or other violent street groups. A deterrence message was conveyed to the high-risk individuals through parole/probation call-in meetings or custom notification meetings. These deterrent notifications included messages that violence was unacceptable, that law enforcement was working to remove individuals from the community who committed violence, and that law enforcement would pull every lever possible to sanction violence committed by the individual or the individual’s group. During these notification meetings individuals were told that social service providers were available to offer support and help individuals get out of a “high-risk life.” During the initial implementation of Detroit Ceasefire in 2013, some challenges were faced with identifying gang-related firearm incidents and gaining intelligence to “pull levels” on the larger group. Changes were implemented starting in the summer of 2015, including expansion of and an additional leadership role in enforcement and intelligence activities for the Gang Intelligence Unit and changes to the structure of weekly meetings.

How was the intervention evaluated?

Detroit Ceasefire was implemented in the two precincts that experienced the highest violent crime levels in the city. The treatment group consisted of 160 census blocks across the 5th and 9th precincts. The program was evaluated using a hypothetical comparison group (i.e., synthetic controls) based on a weighted average of the 518 untreated census blocks from the remaining precincts in the city. The synthetic control approach was employed because Detroit was experiencing changes in its crime trend, facing structural changes, and employing anti-crime initiatives across all parts of the city during the same period that Detroit Ceasefire was implemented. Researchers analyzed data on all fatal and non-fatal shooting incidents from the years 2011 through 2019, with their outcome analysis focusing on Ceasefire’s re-organization and full implementation period (Quarter 3 in 2015 through 2019).

What were the key findings?

When assessing end-of-year differences for the full implementation of Detroit Ceasefire, there were no significant differences between the treatment and synthetic control conditions. At the end of year 1, there were slightly fewer victims aged 15-24 and victims aged 25-34 for the treatment condition, however, this decrease was not statistically significant. By the end of year 4, the treatment and synthetic control conditions were very similar, with the treatment group having slightly more victimizations than the synthetic control group. When evaluating period-specific changes, the only significant results were for Quarter 3 and Quarter 4 of 2016, with significantly fewer victims in the treatment condition than in the synthetic control condition.

What were the implications for law enforcement?

The authors conclude that the effects of Detroit Ceasefire were limited to the first year of its full implementation and that these effects were minimal. They highlight the difficulties in implementing and evaluating focused-based deterrence strategies, noting the challenges researchers faced when trying to isolate the effects of a single intervention. They advise  cities intending to implement a focused-based deterrence program in the future to consider the necessary level of commitment and cooperation for the program’s implementation. Ceasefire requires effective communication of the deterrent message, commitment by prosecutors to reinforce the deterrent message, a timely follow-up to incidents of gang-related violence, and cooperation and commitment among many different agencies.

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