Evidence-Based Policing Matrix
Jurisdiction – McGarrell et al. (2010)
Study Reference:
Location in the Matrix; Methodological Rigor; Outcome:
Jurisdiction; Focused; Proactive; Moderately Rigorous; Effective
What police practice or strategy was examined?
This study evaluates the Project Safe Neighborhoods (PSN) program, which are multi-agency task forces led by U.S. Attorneys’ Offices involving local, state and federal law enforcement, local prosecutors, probation and parole, local service providers and neighborhood leaders and groups. Strategies vary by city, but they all emphasize deterrence and incapacitation through the threat of federal prosecution for illegal gun possession and violent, gang, and drug related offenses involving a firearm.
How was the intervention evaluated?
This study compares 82 cities employing PSN with 170 non-treatment cities. To examine the relationship between PSN implementation and potential changes in violent crime, growth curve regression models were applied to violent crime trends using data from Federal Bureau of Investigation (FBI) Uniform Crime Reports (UCR) that captured Type I offenses for the years 2000–2006.
What were the key findings?
Cities that received high dosages of PSN treatment experienced statistically significant, though modest, declines in violent crime whereas non-targeted cities and sites with low dosage of PSN treatment experienced no significant change in violent crime during the same period.
What were the implications for law enforcement?
The authors suggest that the multi-agency, focused deterrence, problem-solving approach holds promise for reducing violent crime when used at high dosages. At a minimum, these findings call for continued programmatic experimentation with data-driven, highly focused, deterrence-based violence reduction strategies.
Where can I find more information about this intervention, similar types of intervention, or related studies?
- All studies in the Matrix on jurisdictions
- One pager – Impact of PSN on Violent Crime
- One pager – PSN A national strategy to locally address gun violence
- CrimeSolutions Focused Deterrence Practice Profile
- Pulling Levers Systematic Review
- COPS Office Pulling Levers Review
- Project Safe Neighborhoods – Bureau of Justice Assistance
- Project Safe Neighborhoods – Michigan State University