Taylor, B., Koper, C. S., Woods, D. J. (2011). A randomized controlled trial of different policing strategies at hot spots of violent crime. Journal of Experimental Criminology, 7(2): 149-181.
Location in the Matrix; Methodological Rigor; Outcome:
Micro places, General, Proactive, Very Rigorous; No evidence of an effect
What police practice or strategy was examined?
This study examined the effectiveness of directed patrol and problem-oriented policing strategies at hot spots of violence crime in Jacksonville, Florida. This summary focuses on the directed patrol intervention which involved assigning officers to intensely patrol these locations at high-risk days and times. JSO determined the patrol dosage and schedule (i.e., days of week and times of day) for each hot spot based on analysis of the location’s crime levels and high-risk times. During the selected days and times, pairs of officers in separate cars worked one to three hot spots at a time (officers assigned to multiple hot spots covered locations in close proximity). Total officer-hours from the experimental patrols at the saturation/directed patrol locations averaged about 53 per week.
How was the intervention evaluated?
The authors identified 83 hot spots of non-domestic (“street’) violence and randomly assigned them to one of three conditions: 40 control hot spots (usual levels of policing with no special intervention), 21 directed patrol hot spots, or 22 problem-oriented policing (POP) hot spots. Each of these three conditions was maintained for a 90-day period Using incident reports and calls for service, the authors examined the impacts of the patrols and problem-solving interventions on total Part I violence, non-domestic Part I violence, and Part I property crimes in and around the hot spots during the 90-day intervention period and the 90 days following the intervention.
What were the key findings?
Although not statistically significant, reductions in crime in the directed patrol areas ranged from 4–20% for the violence measures (most estimates ranged from 12– 20%) and from 3–13% for the property crime measures. There were also no residual deterrent effects from the patrols in the 90 days following the intervention. This finding is in contrast with the use of POP, which was associated with a 33% reduction in “street violence” (see the separate Jacksonville study brief on POP at hot spots).
What were the implications for law enforcement?
Directed patrol did not produce clear reductions in crime at these hot spots, but the authors cautioned that limitations to their study design (a small sample size and associated low statistical power) may have masked important differences between the directed patrol and control hot spots.
Where can I find more information about this intervention, similar types of intervention, or related studies?