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Neighborhood – McGarrell et al. (2015)

Study Reference:

McGarrell, E. F., Circo, G., & Rydberg, J. (2015) Detroit Project Safe Neighborhoods: Final Project Report. Michigan State University, School of Criminal Justice, Michigan Justice Statistics Center.

Location in the Matrix; Methodological Rigor; Outcome:

Neighborhood; Focused; Proactive; Rigorous; Effective

What police practice or strategy was examined?

The intervention involved the local application of the national Project Safe Neighborhoods (PSN) initiative in two precincts (6th and 8th precincts) of Detroit, Michigan, with high levels of violence. This effort was undertaken by the Comprehensive Violence Reduction Partnership (CVRP), a taskforce made up of members from various local and national law enforcement agencies operating in Detroit. The CVRP utilized an enforcement strategy rooted in long-term investigations of known violent street gangs/offenders and directed patrol at hotspots. First, the research partner would identify chronically violent offenders and locations using data from the Detroit Police Department. Then, the CVRP would respond with aggressive, targeted enforcement, coordinating these efforts with dedicated prosecutors to incapacitate repeat offenders. This involved the CVRP targeting one or two specific gangs using Michigan Department of Corrections (MDOC) parolee/probationer home compliance checks. The CVRP also conducted targeted patrols at hot spots to increase gun seizures and arrest chronic offenders, who were then subject to both state and federal indictments. Finally, the intervention included a crime prevention strategy called Project Sentry, a youth outreach program designed to educate youths in Detroit public schools about the consequences of gun violence. This treatment began in July 2012.

How was the intervention evaluated?

A synthetic control model was used to evaluate the effectiveness of the intervention to compare monthly data from the treatment areas (precincts 6 and 8) with areas of the city that did not receive the treatment. The synthetic control model was constructed to resemble the treatment area before the intervention. In particular, areas outside of the treatment precincts, excluding those that are not populated, were weighted based on a variety of predictor variables, including the armed robbery rate, percentage of vacant homes, percent unemployed, and other demographic characteristics to create a synthetic control area that was comparable to the intervention sites pre-treatment. The intervention was also examined using a more descriptive analysis of crime trends. (NOTE: Only the synthetic control model findings are reported in the Matrix).

What were the key findings?

The results of the synthetic control model indicate a modest impact of the program (the treatment areas showed lower crime rates than the synthetic controls). The authors emphasize the period from July 2014-June 2015, during which the treatment areas experienced a 9% greater reduction in gun crimes when compared to the synthetic control and hypothesize this as evidence of a delayed impact of the intervention strategies.

What were the implications for law enforcement?

The authors suggest that the results of their analysis highlight many of the benefits related to developing partnerships between key stakeholders in order to collaboratively address a specific crime problem. The relationships between various law enforcement agencies, researchers, prosecutors, and other agencies help to promote enhanced communication and maximize the effective utilization of resources in achieving the overarching goal. Conversely, the authors reference obstacles like delays and budget constraints as potential reasons why enforcement actions and subsequent prosecution took time to have an impact at the community-level.

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