Reducing Violence Without Police: A Review of Research Evidence


Executive Summary

Arnold Ventures asked the Research and Evaluation Center at John Jay College of Criminal Justice to review and summarize research on policies and programs known to reduce community violence without relying on police. To accomplish this goal, the Research and Evaluation Center assembled a diverse group of academic consultants across the fields of criminology, social and behavioral sciences, public health, epidemiology, law, and public policy. The group met several times during the summer of 2020 to produce an accessible synthesis of research evidence. Key questions were:

  • Can communities ensure the health and security of residents without depending on law enforcement,
  • What is the strongest research evidence to aid in the selection of violence-reduction strategies,
  • How can community leaders and funding organizations like Arnold Ventures draw upon existing evidence while building even better evidence, and
  • How can funding organizations use this report to elevate discussions about violence, improve outcomes in communities affected by violence, and help local and national partners to identify evidence-based interventions that are ready to be scaled.

The consultants used a broad lens to define community violence as the type of interpersonal violence that occurs in public places, but they considered the personal and structural antecedents of violence as well. By identifying the precursors of violence and emphasizing both their practical salience and theoretical relevance, the group sought to identify the most useful evidence for preventing and reducing community violence.

This report represents the consultants’ best advice for funding organizations and community leaders, but it is not a technical synthesis of research or a meta-analysis of the most rigorous studies. (There are sources for that information already, see, a site hosted for the U.S. Department of Justice.)

This report summarizes the collective judgment of an experienced group of researchers who were free to consider all evidence, unconstrained by the conventional priority given to randomized controlled trials (RCT). The most rigorous studies in the field of community violence are RCTs, but many focus on individual behaviors only, failing to account for the full social context giving rise to those behaviors, including social and economic inequities, institutionalized discrimination, and the racial and class biases of the justice system itself.

To synthesize evidence in an inclusive manner, one must be aware of social context and prioritize solutions that help to address structural impediments while still providing immediate interventions to reduce violence. Unless research evidence is considered in this context, potentially effective strategies may be overlooked simply because they target community-level change rather than individual change, and for that reason are difficult to evaluate and the research literature to back them up is inevitably less rigorous and less prominent.

With these goals in mind, the members of the research group worked collaboratively to identify, translate, and summarize evidence for strategies to reduce violence without police. To identify the most important and potentially effective strategies, the research group placed a high value on programs designed with a clear theoretical rationale and outcomes at specific levels—i.e. individuals, families, neighborhoods (including blocks and street segments), or larger geopolitical boundaries, including cities and counties. Recognizing that evaluation research tends to favor programs aimed at individual behaviors, the group made an effort to include strategies focused on community-level change with the potential to achieve durable, scalable effects.

The research advisory group also focused on the time frame for intervention. Some effective methods for preventing violence take years to reach their maximum effect. Some well-known strategies generate outcomes in a year or two, but that doesn’t make them the best ideas. The research advisory group resisted a systematic bias favoring short-term interventions.

The group identified seven evidence-backed strategies:

Improve the Physical Environment
Place-based interventions that are structural, scalable, and sustainable have been shown to reduce violence and many strategies are economically viable. Increasing the prevalence of green space in a neighborhood, improving the quality of neighborhood buildings and housing, and creating public spaces with ample lighting suitable for pedestrian traffic can be cost-effective ways of decreasing community violence.

Strengthen Anti-Violence Social Norms and Peer Relationships
Programs such as Cure Violence and Advance Peace view violence as a consequence of social norms spread by peer networks and social relationships. Outreach workers, a key part of these interventions, form supportive and confidential relationships with individuals at the highest risk of becoming perpetrators or victims of violence, connecting them with social resources and working to shift their behavior and attitudes toward non-violence. Evaluations suggest these programs may help reduce neighborhood violence.

Engage and Support Youth
Young people, especially young males, account for a disproportionate amount of community violence. Any effort to reduce violence must involve a special focus on youth. Strategies that add structure and opportunities for youth have been shown to decrease their involvement in violent crime. Youth employment, job mentorship and training, educational supports, and behavioral interventions can improve youth outcomes and reduce violence. Some of these strategies require relatively costly individualized therapeutic interventions, but others focused on work and school have been associated with cost-efficient reductions in violence.

Reduce Substance Abuse
Numerous studies show that interventions to reduce harmful substance abuse are associated with lower rates of community violence, and not all strategies involve treatment. Policies to enforce age limits on alcohol access, restrict alcohol sales in certain areas or during specific times, as well as increasing access to treatment have been shown to decrease violent crime.

Mitigate Financial Stress
Financial stability and economic opportunities help to reduce crime. Short-term assistance, especially when coupled with behavioral therapy programs, appears to affect rates of violence and the timing of financial aid plays a role in community safety. People experiencing negative income shocks are less inclined to behave violently when they receive timely financial assistance.

Reduce the Harmful Effects of the Justice Process
The judicial process must be viewed as legitimate for community members to engage effectively with law enforcement in reducing violence. Research suggests that community safety is supported when justice systems operate with transparency, openness, consistency, and trust, and when police departments are willing to address complaints from the community.

Confront the Gun Problem
Implementing comprehensive and uniform gun policies can decrease the use of firearms in violent acts. Violence has been reduced by policy mechanisms that limit access to guns and increase restrictions for individuals with violent crime backgrounds, reduce access to guns by young people, impose waiting periods, and increase required training.

[ read the report ]