Kennedy, L. W., Caplan, J. M., & Piza, E. L. (2015). A multi-jurisdictional test of risk terrain modeling and place-based evaluation of environmental risk-based patrol deployment strategies. Rutgers Center on Public Security, Newark, NJ.
See also Caplan, J.M. and Kennedy, L.W. (2016). Risk Terrain Modeling: Crime Prediction and Risk Reduction. (University of California Press).
Location in the Matrix and Methodological Rigor:
Micro places, Focused, Proactive; Rigorous; Effective
What police practice or strategy was examined?
The quasi-experimental study evaluated police intervention strategies targeted at high-risk micro-level environments derived from risk terrain modeling (RTM) across 5 cities. Summarized here is the Newark, NJ study, which focused on gun violence. The RTM analysis yielded 11 significant risk factors associated with gun violence, including narcotics arrests, foreclosures, restaurants, gas stations, convenience stores, food take-outs, bars, abandoned properties, schools, liquor stores and problem housing. Using this information, the Newark Police Department (NPD) designed its intervention to generate checks and manager contacts at three business types: Restaurants, Food Take-Outs, and Gas Stations. A task force of three officers under the supervision of a Lieutenant visited these businesses located within the target area (identified by RTM) on a daily basis, during which officers checked in with the on-duty manager and obtained signatures for record keeping. The intervention lasted for approximately three months.
How was the intervention evaluated?
Control street units were identified using a Two Nearest Neighbors propensity score matching technique. Matching variables included whether the street unit intersected a high-risk street unit or a high-risk cell as identified by the RTM analysis, whether the unit was a segment or intersection, the concentrated social disadvantage and racial heterogeneity in surrounding census block group, as well as pretest levels of crime and proactive police actions. Gun violence incidents including homicide, aggravated assault, and robbery incidents in which the suspect used a firearm during the three-month posttest period were compared to the figures during the same period from the previous year in the treatment and control areas.
What were the key findings?
The strategy generated a statistically significant 35% reduction of gun violence in the target area as compared to the control area. The average reduction experienced by target-area street units was significantly greater than that experienced in the matched control units. Finally, the regression analysis at micro-level places further found that the intervention activities were associated with decreased crime levels in high-risk portions of the target areas as well as a slight diffusion of benefits.
What were the implications for law enforcement?
The authors suggest that the NPD task force’s intervention activities, which predominately involved meet-and-greets with business managers, can be effective when focused on facilities located in high-risk places as identified by risk terrain modeling.
Where can I find more information about this intervention, similar types of intervention, or related studies?