Individuals – Spergel et al. (2002)

Study Reference:

Spergel, I. A., Wa, K. M., & Sosa, R. V. (2002). Evaluation of the Mesa Gang Intervention Program (MGIP). Washington, DC: Office of Juvenile Justice and Delinquency Prevention. Washington, DC: Office of Juvenile Justice and Delinquency Prevention.


Location in the Matrix; Methodological Rigor; Outcome:

Individuals; Focused; Proactive; Moderately rigorous; Effective


What police practice or strategy was examined?

This report evaluated the Office of Juvenile Justice and Delinquency Prevention’s (OJJDP) Comprehensive Community-Wide Approach to Gang Prevention, Intervention, and Suppression Program as it was implemented in Mesa, Arizona. This is a model gang program promoted under grants from OJJDP. The OJJDP model involves multiple agencies interactively addressing individual youth, family members, and gang peers. The five core model strategies are community mobilization, social intervention, provision of social opportunities, suppression/social control, and organizational change and development. In an effort to implement this model under an OJJDP grant, the Mesa Police Department (MPD), the lead agency, collaborated with the Maricopa Juvenile and Adult Probation Departments, the Mesa School District, and United Way social agencies in the development of a 5-year gang prevention and suppression project entitled the Mesa Gang Intervention Program (MGIP). MGIP utilized a case-management approach involving a team of gang police, probation officers, case managers and outreach youth workers with the aim of providing social-intervention services and control activities to reduce offending. These services and activities included individual and family counseling, group discussions, referrals to a variety of community agencies, and surveillance, supervision, monitoring, and arrest.


How was the intervention evaluated?

This intervention involved a case-management approach in which a team of gang police, probation officers, case managers, and outreach youth workers monitored and provided social-intervention services to 258 juveniles, primarily male Latinos between the ages of 12 and 20. Most were gang members on probation who were nonviolent offenders. The authors compared these youth with 96 control youth (who received no program services) from three different areas with gang problems. The study used interviews, self-reports of offending, and police arrest histories for the program and non-program youth. The study also examined changes in juvenile crime in the neighborhoods with the program youth and the neighborhoods with the control youth by monitoring arrests over a four-year program period compared to an equivalent four-year pre-program period.


What were the key findings?

The program youth had arrest levels 18% lower than the comparison youth over a 4-year period. The targeted program neighborhoods also experienced a 10.4% greater reduction in selected juvenile-type crimes compared with an average of such crimes in the three comparison neighborhoods.


What were the implications for law enforcement?

The study suggests that multi-faceted, multi-agency interventions involving both prevention and suppression efforts are effective in reducing gang crime. The authors suggest that the effectiveness of the program was due in large measure to the range of social-intervention services provided by project staff, the high quality of project leadership, commitment to the model (by OJJDP), and to the high level of collaboration among Mesa institutions in respect to the emerging gang problem.


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