Micro Places – Sherman et al. (1989)

Study Reference:

Sherman, L., Buerger, M., & Gartin, P. (1989). Beyond dial-a-cop: A randomized test of Repeat Call Policing (RECAP). Washington, DC: Crime Control Institute.


Location in the Matrix; Methodological Rigor; Outcome:

Micro places; Focused; Proactive; Very Rigorous; Mixed effects


What police practice or strategy was examined?

This study evaluated the effectiveness of a proactive police strategy known as Repeat Call Address Policing (RECAP). The strategy aimed to target specific addresses that had high frequencies of calls for service of predatory crime, disorder, and persons in need of assistance. RECAP consisted of a special unit of four patrol officers and one sergeant who were assigned to conduct problem-oriented work on high-frequency call addresses for one year. The officers were trained to carry out four steps for this intervention: the diagnosis of the problems, the development of an action plan, the implementation of the plan, and weekly follow-up of call trends at the address. Commonly used efforts included attempts to empower resident property managers to deal with problem tenants, reducing drug activity disorder at particular places, condemning apartments with no locks on the doors, persuading the owner of a high-crime parking garage to raise the monthly fee to finance fencing, or organizing an undercover investigation of drug dealing and serving of intoxicated persons in a high-crime tavern.


How was the intervention evaluated?

A randomized controlled experiment was conducted to evaluate the RECAP strategy. All addresses were sorted from most to least frequent call volume per address from December 1985 to December 1986. The researchers then selected the top 250 commercial and residential addresses. Before the final list was finalized, officers agreed to visually inspect any locations adjacent to or otherwise influenced by police interventions at another address on the list. The purpose of these inspections and the review of addresses from their knowledge was to ensure the independence of each address from all others, thus eliminating treatment contamination of the control group once it was chosen. Before randomization, the authors block the sample of 500 addresses into half commercial and half residential. A computerized random numbers generator was employed to assign the top 250 commercial and residential addresses to 125 experimental and 125 controls. Both residential and commercial samples were subjected to a variety of levels of effort. Some addresses had as little as one contact during the entire year. Others had weekly contacts initiated by the citizens.


What were the key findings?

The findings of this study are mixed. Pre-post differences in calls at the commercial addresses that received RECAP showed no difference from the control group. Pre-post differences in calls at the residential addresses that received RECAP showed a 15% greater reduction than the control group (p< .05) in the first six months, which declined to a 6% greater reduction after one year.


What were the implications for law enforcement?

The authors believed that the strategy is sound and can have impacts on high-volume call locations (especially residential ones and with disorder calls). However, more specific diagnostic and tactical tools are needed for broader success at crime prevention and call reduction. They note that while generally unsuccessful, some of the commercial locations did have isolated successes, such as the liquor license suspension of a bar implicated in hundreds of robberies and several recent murders.


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