Evidence-Based Policing Matrix
Neighborhood – Nunn et al. (2006)
Study Reference:
Location in the Matrix; Methodological Rigor; Outcome:
Neighborhood; Focused; Proactive; Moderately Rigorous; Mixed effects
What police practice or strategy was examined?
The strategy examined was a covert police interdiction using a problem-solving approach in an inner-city drug market in the Brightwood neighborhood of Indianapolis. Officers in the Metro Drug Task Force (MDTF) used surveillance and spoke with beat officers and community members to identify over two dozen people suspected of representing the largest source of the drug problem in that area as well as other areas of the city. Individuals were then confirmed as chronic offenders through criminal history checks. Using wiretaps, aerial and on-the-ground surveillance techniques, and controlled purchases in the neighborhood, officers were able to build an affidavit requesting multiple search warrants, arrest warrants and property seizure warrants. On a single “interdiction day” (April 5, 1999) approximately 175 officers executed 33 residential search warrants, 21 individual federal arrest warrants, 5 individual state arrest warrants, and 4 seizure warrants for vehicles that had been used for drug trafficking activities.
How was the intervention evaluated?
The interdiction was examined using a pre-post multiple time series design with a non-equivalent control group, and used police calls for service as the outcome criteria. The data series examining calls for service is treated as an interrupted time series, covering the period between April 5, 1998 to April 5, 2001. A neighborhood that did not host a special interdiction during the evaluation period was chosen as a non-equivalent control.
What were the key findings?
Results indicated that in comparison to the Westside control neighborhood, total calls for service in Brightwood declined, and more specifically, serious crimes. One exception was noted: calls for service for drug activity actually increased in Brightwood but declined in the non-interdiction area of Westside. Long-term findings indicated very little decay in the crime declines in the Brightwood interdiction neighborhood after 2 years in comparison to the Westside control neighborhood.
What were the implications for law enforcement?
The authors suggest that covert interdiction for drug offenders can impact serious crimes by targeting a specific group of chronic offenders. The increase in drug calls for service could indicate an increase in citizen willingness to call the police (or less fear), or it could indicate a replacement effect of new drug dealers in an area. Caution about these results should be noted given the comparison to a non-equivalent comparison group.
Where can I find more information about this intervention, similar types of intervention, or related studies?