Rosenfeld, R., Deckard, M. J., & Blackburn, E. (2014). The effects of directed patrol and self-initiated enforcement on firearm violence: a randomized controlled study of hot spot policing. Criminology, 52(3), 428-449.
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?
The study examined directed patrol and enforcement activities conducted at firearm violence hot spots in St. Louis, Missouri. This analysis focuses on directed patrol alone. Officers assigned to the treatment area were instructed to patrol slowly through the area and to avoid engaging in self-initiated activity, unless a crime was in progress or citizen or officer safety were at risk. They were required to patrol each hot spot at least three times during an 8-hour shift and to remain in that area for approximately 15 minutes. The intervention was restricted to the evening (3 p.m. to 11 p.m.) and overnight shifts (11 p.m. to 7 a.m.), when firearm violence was most frequent.
How was the intervention evaluated?
Four hot spots with the highest frequency and spatial concentration of firearm violence in each of the eight districts were randomly assigned, with one assigned to the directed patrol treatment described here, one to the directed patrol with enforcement activities condition, and two to the control condition. No instructions were given to officers in the control areas. Firearm aggravated assault and firearm robbery incidents were measured 9 months prior to the intervention and during the 9 months of the intervention at both treatment and control sites to determine the effect of directed patrol. In addition, the study tested displacement to other types of crime (non-firearm violent crime), other time periods (during the day shift), and surrounding areas (within a 500-ft radius of the hot spot boundaries).
What were the key findings?
The directed patrol intervention had no significant impact on any of the outcome measures. Displacement analyses were not conducted for this treatment because of the lack of a significant crime decline.
What were the implications for law enforcement?
The authors suggest that enhanced directed patrols, when not accompanied by other enforcement activity in hot spots, did not impact firearm assault or firearm robbery.
Where can I find more information about this intervention, similar types of intervention, or related studies?