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Neighborhood – Tita et al. (2003)

Study Reference:

Tita, G., Riley, K. J., Ridgeway, G., Grammich, C., Ambrahamse, A. F., & Greenwood, P. W. (2003). Reducing Gun Violence: Results from an Intervention in East Los Angeles. Santa Monica, CA: Rand.

Location in the Matrix; Methodological Rigor; Outcome:

Neighborhood; Focused; Proactive; Moderately Rigorous; Effective

What police practice or strategy was examined?

This study replicates the Boston Gun Project designed to reduce gun and gang violence in the Hollenbeck area of Los Angeles. The intervention targeted areas with high levels of gang violence with increased uniformed patrols in the geographic area of a “triggering” event (any event the Hollenbeck working group believed might lead one gang to retaliate against another). The intervention also used more stringent enforcement of housing codes and of public housing eligibility rules; more stringent enforcement of parole and probation conditions; and referral of gun law violations to Federal prosecutors.

How was the intervention evaluated?

The intervention was introduced to five reporting districts in the Hollenbeck area with the remaining reporting districts serving as the control group. The intervention was evaluated using a quasi-experimental design, examining changes in violent crime, gang crime, and gun crime. Three types of comparisons were made across different spatial units matched by key characteristics such as crime rates and poverty. The analysis compared changes in crime from six months prior to the triggering event (pre-intervention period), the four months in which all parts of the intervention were applied (suppression period), and the two months in which only selected parts of the intervention were applied (deterrence period).

What were the key findings?

Findings varied across the comparison areas and also different with regards to declines in the suppression versus the deterrence period. In some targeted areas, violent crime was reduced, but not gang crime or gun crime. In another comparison, gun crime declined in the suppression period but was not sustained in the deterrence period. It does not appear that the intervention displaced crime from the targeted areas and gangs to others; rather, crime decreased in surrounding communities as well.

What were the implications for law enforcement?

The authors found that the intervention was not implemented as designed and it did not develop dynamically in response to changing needs. Additionally, one of the main findings of the evaluation indicated that the agencies involved in the Los Angeles intervention did not take an ownership interest in the intervention. The authors suggest that if interventions of this nature are to be successful, they must gain the support of all agencies involved.

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