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Groups – Engel et al. (2013)

Study Reference:

Engel, R. S, Tillyer, M. S., and Corsaro, N. (2013). Reducing gang violence using focused deterrence: Evaluating the Cincinnati Initiative to Reduce Violence (CIRV). Justice Quarterly, 30(3), 403-439.

Location in the Matrix; Methodological Rigor; Outcome:

Groups; Focused; Highly Proactive; Moderately Rigorous; Effective

What police practice or strategy was examined?

The Cincinnati Initiative to Reduce Violence (CIRV) aims to reduce homicides and gun-related gang violence by specifically targeting at-risk gang members to be sure they know the consequences of violence. The CIRV is a coalition of law enforcement, academics, medical professionals, advocates, and community leaders with formally defined roles and responsibilities. The CIRV strategy was designed based on previous programs (implemented in Boston, Minneapolis, Stockton, East Los Angeles, and elsewhere) and incorporated lessons learned from the challenges those programs faced. In a three-pronged approach, the CIRV team sought to increase the costs of becoming involved in violence by using focused deterrence and prosecution, providing alternatives to violence, and changing group norms toward violence. Communities with high levels of gun violence or known gang territories were targeted.

The CIRV Law Enforcement Team identified 2,431 individuals who were members of violent groups. Those under probation or parole were required to attend notification meetings, where representatives from the CIRV Law Enforcement team communicated the consequences of violence. Similar sessions were also held in prison and during home visits. The CIRV team informed targeted individuals that their whole group would be prosecuted for any associated acts of violence (not just the individual). Any such arrests and charges were made known as examples to other would-be offenders, demonstrating officers’ commitment to what they said.

The social services component of the program involved providing job readiness training to criminally-involved persons and delivering other social services to target antisocial attitudes, peers, behaviors, and personality factors. A team of Street Advocates recruited at-risk individuals for social services and conducted activities related to violence interruption, mediation and spreading non-violence messages in the community. The CIRV Services Team met monthly to review participants’ progress.

Finally, the CIRV Community Engagement Team encouraged community members to participate in various programs and events in order to strengthen collective efficacy and informal social control.  The team organized violence prevention programs, outreach activities, funerals and vigils, educational trainings, and other events aimed at community involvement.

How was the intervention evaluated?

Researchers examined violent crimes across the city between 2004 and 2010, comparing crime trends before CIRV implementation (2004-2007) and during CIRV implementation (2007-2010), as well as at distinct time points 24 months and 42 months after the intervention. Gang-involved homicides (which CIRV targeted) were compared to homicides that were not related to gang activity as a control measure. Fatal and non-fatal shooting incidents were also examined and compared to trends in non-shooting violent offenses. Researchers expected the intervention to reduce shootings but could not discern whether shootings were gang-related. Researchers also tracked the number of social services interventions that occurred during CIRV implementation.

What were the key findings?

Gang-related homicides (which CIRV targeted) declined after the CIRV program was implemented, while non-gang-related homicides (which CIRV did not target) increased slightly. Gang-related homicides had decreased 37.7% by 24 months after the start of the intervention, and continued declining to a 41.4% reduction after 42 months. Even after the intervention ended, gang-related homicides continued to decrease, demonstrating lasting effects of the CIRV efforts. In addition, shootings declined 22% following the intervention (for both follow-up periods), while non-shooting violent offenses were unaffected. Analysis indicated that law enforcement efforts were more influential to the reduction in violence than social services; however, the researchers speculated that social services may be important for sustaining crime reduction in the long-term.

What were the implications for law enforcement?

This study demonstrates that focused deterrence strategies can be effective at reducing violent crime. This case also serves as an example of how to maintain such strategies over time, using a formally-structured organization to sustain its continued operation.

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