Evidence-Based Policing Matrix
Neighborhood – Azrael et al. (2013)
Study Reference:
Location in the Matrix; Methodological Rigor; Outcome:
Neighborhood; Focused; Proactive; Moderately Rigorous: Effective
What police practice or strategy was examined?
The Milwaukee Homicide Review Commission (MHRC) was established in May 2004 to address the city’s lethal violence problem. It is a multi-tiered intervention with four levels, each of which involves participation by a different set of agencies and stakeholders. Level 1 is the front-line response to a homicide or shooting (consisting of real-time response couples with provision of services to the victim’s families); Level 2 is a criminal justice review, in which each month’s homicides are reviewed; Level 3 is the community service provider reviews, in which public health and social service agencies provide additional information about specific homicides and the community contexts in which they occur; Level 4 are semi-annual community meetings to inform the local community about the “shape” of district-level homicide and to solicit buy-in for community based homicide reduction initiatives.
The MHRC reviewed 173 homicides and 99 non-fatal shootings. Overall, the homicide review process revealed that homicides in the City’s intervention districts were largely clustered in very specific places, such as in and around taverns, and among active offenders who were very well known to the criminal justice system. Homicides were often the outcome of an ongoing dispute between individuals or groups and involved respect, status, and retribution as motives. Recommended initiatives for the police included problem-oriented policing efforts to improve, expand, or enhance current practices related to managing high-risk people and places, such as dealing with violence at taverns, preventing violence and nuisance properties, and enhanced community supervision of high-risk offenders. Individual interventions were not evaluated in this study, only the impact of the overall MHRC process. City districts were matched based on demographic and crime profiles, and one district from each pair was randomly allocated to the MHRC process. Three districts implemented the program while the remaining four served as control districts.
How was the intervention evaluated?
The impact evaluation consisted of two components: a comparison of the quality of information collected about homicides using existing data as compared to MHCR data, and a statistical analysis of the crime reduction impact of implemented violence prevention strategies in the treatment districts relative to the control districts. The impact evaluation was designed to measure the value added by the MHRC process, and was unable to parse out the varying effects of the specific initiatives implemented. This summary only focuses on the crime reduction impact. Time series of monthly counts of homicides in the treatment and control districts between January 1999 and December 2006 were examined to determine whether the MHRC process was associated with reductions in homicides. Regression analyses, controlling for secular trends, seasonal variations, population changes, and violent crime rate trends, were used to estimate changes in the monthly counts of homicide events in the treatment districts and control districts after MHRC interventions were implemented.
What were the key findings?
The impact evaluation revealed that the MHRC process was associated with a statistically significant 52% decrease in the monthly count of homicide in the treatment districts. The control districts experienced a non-significant 9.2% decrease in homicide, controlling for other covariates.
What were the implications for law enforcement?
Results from this study should be taken with caution. It is uncertain which part of the MHRC process contributed to the decrease in homicides in the treatment district, and whether the decline was related to the MHRC process. However, processes like MHRC could help agencies better understanding the nature of urban homicide problems, and encourage collaboration with others in crafting interventions to address underlying risks, and implementing innovative strategies to address these risks.
Where can I find more information about this intervention, similar types of intervention, or related studies?