SPI Findings

2020 SPI Map and Findings graphic

Learn more about SPI site successes as it relates to gun violence, violence reduction, technology, mental health, and opioid abuse through our SPI Successes One-Pagers or using the below table.

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SPI Findings

SiteImplementationResearch Design & FindingsTopic
Boston, MA2009

The Boston SPI addressed violent crime, especially robberies and assaults committed with guns, using community policing and problem-oriented policing Safe Streets Teams (SSTs).

  • Completed 28-year longitudinal analysis of violent crime to identify 13 chronic hot spots.
  • Targeted SSTs, consisting of a sergeant and six patrol officers, in hot spots.
  • Deployed nearly 400 different situational/environmental, enforcement, and community/social service techniques to identify and address recurring problems.
Research Design

A quasi-experimental design with propensity score matching (statistically based matching of target sites to control/comparison sites).


More than 17% reduction in violent crime.

More than 15% reduction in aggravated assaults.

More than 19% reduction in robberies.

Gun Violence, Violence Reduction
Boston, MA2011

The Boston SPI implemented the Boston Homicide Clearance Intervention to improve homicide clearance rates and investigations.

  • Conducted spatial analysis on 314 homicide victimizations.
  • Convened a Homicide Advisory Committee.
  • Expanded the police department homicide unit by 36% to include an additional detective, a crime analyst, and two Victim-Witness Resource Officers on each squad.
  • Updated 40-hour crime scene response and investigation in-service training.
Research Design

Process evaluation of homicide protocols, impact evaluation during the implementation period, overall outcome evaluation of clearance rates.


9.8% increase in homicide clearance rates.

18.4% increase in adjusted homicide clearance rates (including cases awaiting a grand jury).

Violence Reduction
Cambridge, MA2011

The Cambridge SPI, a collaborative effort with the cities of Everett and Somerville, called RASOR (Regional Analytics for the Safety of Our Residents), focused on preventing victimization and social harm.

  • Created partnerships with case managers, social service providers, other criminal justice agencies, and research staff to collectively cultivate a focused deterrence strategy.
  • Examined violent criminal and arrest histories as well as social harm to identify impact players.
  • Developed detailed case profiles on potential candidates and assigned each a case manager.
  • Conducted notification meetings and delivered resources.
Research Design

Outcome evaluation and process evaluation of the randomized experimental design.


No statistically significant differences in time to arraignment between RASOR and control.

The more time invested by case management and services, the longer the survival time of individuals participating in RASOR (i.e., did not reoffend as quickly as the control group).

Violence Reduction
Glendale, AZ2009

The Glendale SPI sought to reduce crime and disorder pertaining to convenience store thefts in the southeast quadrant of the city. 

  • Provided officers with 20 hours of POP training using the SARA (Scanning, Analysis, Response, and Assessment) model to identify and reduce crime.
  • Analyzed crime to find that crime centered at six local convenience stores.
  • Implemented a three-pronged response that included engagement with store leadership, prevention strategies (Crime Prevention through Environmental Design or CPTED), and suppression strategies.
Research Design

Pre/post analysis with multiple units and multiple control groups, interrupted time series analysis of convenience stores.


Decline in calls for service in 5 of 6 target stores.

18% reduction in direct costs for officer response and estimated decrease of more than $1.9 million in victimization costs.

Sustained reduction in 4 of 6 target stores (nearly 20% in calls for service overall, two years after the intervention).

Violence Reduction
Glendale, AZ2011

The Glendale SPI continued the efforts of its prior project by focusing POP efforts on problem offenders and organizational retail theft.

  • Conducted intensive problem analysis of calls for service data, resident surveys, and social and physical disorder surveys.
  • Used new data collection protocols and social network analysis.
  • Implemented traditional crime prevention strategies, as well as CPTED, outreach and education, counter insurgency, and informal focused deterrence.
Research Design

Bivariate analysis and interrupted time series analysis.


Identified and targeted prolific offenders, and generated short-term, notable declines in several micro hot spots.

27% reduction in calls for service in a target area (large mall) and short-term 15% reduction in calls for service in a target apartment complex.

Violence Reduction
Kansas City, MO2012

The Kansas City SPI addressed violent crime, particularly gun violence, using a model called the Kansas City No Violence Alliance (KC NoVA).

  • Used social network analysis and group audits to identify violent offender groups (and their frequent associates).
  • Implemented a full range of interventions (e.g., offender notification sessions, enhanced monitoring by patrol officers, strategic federal prosecution, intensive probation and parole supervision, social services).
  • Collaborated with numerous criminal justice stakeholders.
Research Design

Bivariate analysis and interrupted time series analysis to assess the impact of the focused deterrence pulling levers strategy.


40% reduction in homicide.

19% reduction in gun-related aggravated assaults.

Gun Violence, Violence Reduction
Los Angeles, CA2009

The Los Angeles SPI addressed gun-related violence using Operation LASER (Los Angeles’ Strategic Extraction and Restoration Program).

  • Targeted violent repeat offenders and gang members who commit crimes in target areas.
  • Used intelligence-driven location- and offender-based tactics.
  • Implemented a Crime Intelligence Detail, composed of sworn officers and a local crime analyst, to create proactive, real-time intelligence briefs called Chronic Offender Bulletins.
  • Directed patrol, specific missions, and enhanced surveillance.
Research Design

Interrupted time-series analysis, which assesses whether the interventions in target areas had an effect on crime while controlling for previous trends. (Research evaluation is ongoing.)


22.6% reduction in homicides per month in the target division.

5.2% reduction in gun crimes per month in each reporting district of the target division.

Gun Violence, Violence Reduction
New Haven, CT2011

The New Haven SPI addressed rising violent crime and local shooting incidents in a persistently violent neighborhood in the city.

  • Modeled risk terrain to determine areas with the highest risk of violent crime.
  • Had 13 weeks of supplementary, focused foot patrols.
  • Increased use of data-driven decision making (e.g., daily “flash sheets” with maps, crime data, and other data).
  • Engaged community, particularly specific block groups.
  • Modified problem-oriented policing techniques (e.g., patrol officers identified issues such as street lighting and neglected properties, and supervisors implemented responses).
Research Design

Pre-intervention, intervention, and post-intervention analysis in target and control areas.


During intervention, 19% reduction in violent crime at the neighborhood-level and 36% reduction in violent crime in high-risk areas.

13 weeks following the intervention, 41% violent crime reduction at the neighborhood level and 56% reduction in the high-risk areas.

Gun Violence, Violence Reduction
Philadelphia, PA2009

The Philadelphia SPI tested the impacts of three police strategies in violent crime hotspots (foot patrols, POP, offender-focused policing).

  • Gave captains discretion for implementing foot patrols as long as each target area was patrolled a minimum of 8 hours a day, 5 days a week, for 12 weeks.
  • Worked with the community, analyzing and implementing strategies for specific problems.
  • Used Criminal Intelligence Unit officers to identify repeat offenders, who then received frequent contact using a variety of strategies.
Research Design

Process and outcome evaluation of the randomized control design


Offender-focused strategy outperformed foot patrol and problem-solving strategies.

Compared to the control areas, the treatment areas that received the offender-focused strategy experienced a 22% decrease in violent crime, and a 31% decrease in violent street felonies.

Violence Reduction
Phoenix, AZ2011

The Phoenix SPI aimed to improve relations with minority communities by developing a body-worn camera (BWC) program.

  • 50 officers were provided cameras as part of the study and were evaluated from January 2012 – July 2014.
Research Design

Process and outcome evaluation, pre- and post- deployment


From pre- to post-deployment, officers with BWCs experienced a 22.5 percent decline in officially recorded complaints, while across all other precincts there was a 45.1 percent increase in complaints.