Micro Places – Collazos et al. (2021)

Study Reference:

Collazos, D., García, E., Mejía, D., Ortega, D., & Tobón, S. (2021). Hot spots policing in a high-crime environment: An experimental evaluation in Medellin. Journal of Experimental Criminology, 17, 473-506.

Location in the Matrix; Methodological Rigor; Outcome:

Micro places; General; Proactive; Rigorous; Mixed effects

What police practice or strategy was examined?

This study examined the deterrent effects and potential displacement of hot spots policing in Medellín, Colombia. Officers were instructed to intensify patrols in hot spot street segments (seven visits per day for roughly 15 minutes each), by conducting everyday law enforcement activities (e.g., criminal record checks, arrests and seizures, and community visits). The intervention spanned six months, from May 4 through November 19, 2015.

How was the intervention evaluated?

The study identified 967 high-crime street segments. Contiguous high crime streets were joined to create a total of 817 hot spots, of which 334 were randomly assigned to receive intensive patrol, and 483 served as a control group. Researchers categorized control hot spots based on their distance to the nearest treatment hot spot to examine spillover at multiple distances: 0-250 meters, 250-500 meters, and more than 500 meters. The researchers also examined aggregate effects citywide. The intervention was evaluated using data on reported crimes and a survey of Medellín citizens living on the 967 hot spots (two to three residents per street) before and after the intervention. Perceptions of security, satisfaction with policing services, and victimization were measured in the survey.

What were the key findings?

The study found a significant reduction in reported car thefts on targeted streets, but no change in motorbike thefts, personal robberies, homicides, or assaults. Notably, there was no evidence of crime displacement; instead, there was a diffusion of benefits, indicated by decreased car thefts in adjacent hot spots. Overall, the intervention reduced car thefts citywide. In terms of security perceptions, there was a notable increase during the intervention period, but this effect was not extended post-intervention.

What were the implications for law enforcement?

This study provides nuanced insights into the body of research on hot spots policing, which is primarily based on studies in the United States, by demonstrating its unique impact in a different context, Medellín, Colombia. The authors suggest that these outcomes may be attributed to the specific local crime patterns and the police-to-population ratio in Medellín. These findings emphasize the importance of tailoring policing strategies to the distinct contexts, in order to effectively optimize the allocation of police resources for crime reduction. The authors also highlight the importance of monitoring procedures to ensure high compliance with protocols surrounding hot spots deployments.

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