SPI Findings

2022 SPI Map and Findings graphic

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


SPI Findings

SiteImplementationResearch Design & FindingsTopic
Portland, OR2014

Through a multi-agency, collaborative effort, the Portland Police Bureau (PPB) worked in coordination with the Mayor’s Office, local academics, and community partners to reduce crime and build community relationships primarily through community engagement patrols (CEP).

Research Design

Ninety high crime areas were randomly assigned to receive none, two, or four 15-minute supplemental CEPs a day for a three month period. Offense reports, CAD data, resident surveys, officer focus groups, and officer surveys were used to conduct process and outcome evaluations of the NI-Loc program. 

  • Results indicate that the NI-Loc intervention did not affect crime, calls for service, or public perceptions of police, in treatment areas compared to controls.

Community Engagement
Roanoke County, VA2015

The SPI evaluated the effects of mobile crisis team in an experimental context to enhance police response to people with mental illness. The intervention sought to understand and improve Roanoke County Police Department's response to calls for service (CFS) involving individuals experiencing mental health (MH) crises in Virginia’s primarily rural Roanoke Valley.

Research Design

An experimental intervention testing the efficacy of a police-mental health provider co-responder model for addressing mental health-related calls for service.

  • There were no significant reductions in the numbers of calls for service and mental health calls between the treatment and control groups during the treatment and post-treatment periods
  • However, those who completed some treatment appeared to be high-utilizers of police resources before the intervention. Those who completed some treatment show decreased patterns in general calls for service and mental health calls compared to the dropouts.
Mental Health
Rochester, NY2012

The Rochester SPI intervened in retaliatory gun violence.

  • Developed a formal process to document, analyze, and disseminate information about potentially violent retaliatory disputes (including shooting incident data and conducting focus groups).
  • Created an on-scene dispute assessment tool to characterize incidents by retaliation risk.
  • Deployed investigative, place-based, and offender-based interventions for high-risk violent-retaliatory disputes.
Research Design

Examination of descriptive statistics, correlation coefficients, and logistic regression models.


The evaluation validated the risk assessment tool as a predictive device: for every one-point increase in the assessment tool score that a dispute received, the odds of violence occurring in that dispute over time increase by 29%.

Gun Violence, Violence Reduction
Sacramento County, CA2016

The Sacramento SPI implemented a Homeless Outreach Team (HOT). The overall objective of the SPI-HOT pilot was to develop a new service & community-oriented policing approach for addressing homelessness that de-emphasizes enforcement strategies. Three part-time deputies collaborated with various social services to provide street outreach services to individuals and families experiencing homelessness in select “hot spots” of the county – areas identified by Sheriff’s analysts and the research partner as having high levels of homelessness.

Research Design

The intervention was intentioned to result in a series of staggered short-term and intermediate outcomes that would over time contribute to increase safety and collective efficacy in the community around issues of homelessness (the long-term impacts). The evaluation also conducted a process evaluation on implementation of HOT.

  • There was some evidence that calls for service dropped in response to the SPI-HOT team’s work, and that calls for service did not simply increase in adjacent areas.
  • The HOT initiative clearly achieved the goal of developing stronger relationships between the Sacramento Sheriff’s Office and public and non-profit organizations who work with the same homeless population.
  • There was limited evidence that activities by HOT have resulted in substantial institutional and cultural change across the Sherriff’s Office and its other patrols.
Community Engagement, Homelessness
Savannah, GA2009

The Savannah SPI addressed increases in violent crime rates through the Savannah Impact Project (SIP), an intensive reentry and monitoring program focused on high-risk offenders.  

  • Identified hot spots and repeat violent offenders through data analysis to address specific problems.
  • Collaborated with police, parole, and probation to provide intensive case management.
  • Included “wrap-around services” providing treatment and offender reentry services.
Research Design

Pre-post impact analysis, assessment of service provision


16% reduction in violent crime at the Central Precinct (target area).

Exploratory analyses found that providing services could reduce the likelihood of future crimes.

Interviews concluded that SIP was effective because of the multi-agency collaboration and ability to balance treatment and enforcement approaches.

Violence Reduction
Shoreline, WA2015

This SPI developed the Response Awareness, De-Escalation, and Referral (RADAR) effort that was aimed to institutionalize department-wide and regional information sharing about community members with behavioral health issues or developmental disabilities (BH/DD) who may be at increased risk of violence or use of force; and offer opportunities for outreach and connection to services and resources through a mental health “navigator.”

Research Design

A quasiexperimental design based on propensity score matching (PSM) methods in which RADAR response plan recipients would be matched with similarly-situated people in a comparison jurisdiction to compare outcomes accompanied by a process evaluation. 

  • RADAR had a positive influence on Shoreline Police Department’s culture in terms of changing attitudes and responses to people with BH/DD.
  • The evaluation did not find significant effects on rates of mental health-related calls for service or incidents.
  • Use of force was lower after RADAR was implemented, but this was not statistically significant.
Mental Health
Toledo, OH2014

The Toledo Police Department organized a prolific offender unit, entitled the Special Intelligence Group (SIG), consisting of one sergeant, four detectives, and a crime analyst. This unit was trained and equipped to gather intelligence and conduct undercover surveillance of prolific serious offenders. The research partners developed and tested an empirically based Prolific and Priority Offender (PPO) Scoring Matrix – a risk assessment tool for identifying those most at risk of committing a new robbery, burglary, or aggravated assault offense within the next year.

Research Design

A quasi-experimental research design, examining the numbers of reported crimes within the geographic area identified as the “awareness space” of all of the prolific offenders as well examining reported crimes and calls for services within these areas. 


Implementation of the prolific offender program activities coincided with statistically significant reductions in the specific crimes targeted by the program.

  • Robberies declined 3.9%, burglaries declined 20.1%, and aggravated assaults declined 16.1% in these specific geographical areas.
  • Overall reports of crime decreased 1.3%, auto thefts decreased 8.5%, and thefts from autos decreased 14.1%, and total calls for police services decreased 3.1% within these awareness spaces after the project began.
Violence Reduction