Philadelphia has solutions — based on concrete evidence — that can reduce its number of shootings. The problem is we’ve been funding the wrong solutions instead.

When Gov. Tom Wolf signed an executive order in August to make sweeping changes addressing community gun violence, I was optimistic that his stated push to view the problem from “all angles” would include research-based evidence. As part of these efforts, on Dec. 5, the Council on Gun Violence created by the governor held a public hearing at Temple University. I took the opportunity to advocate for an evidence-based approach that has been sorely lacking from the conversation.

To date, Philadelphia has invested too much in programs and ideas that lack rigorous supporting evidence and are not tied specifically to reducing shootings. For instance, months of strategic planning under the city’s Youth Violence Prevention Collaborative by 2016 mostly only yielded piecemeal investments to increase summer jobs and job training for youth and young adults with no demonstrated link to reductions in violence. While Philadelphia has seen rising gun violence in the last three years, other American cities have reduced their levels of violence because they are willing to fund programs with strong evidence and scale those programs when evaluations show success.

The existence of proven interventions suggests that cities can make a real difference. We have seen this in New York City, with millions of dollars dedicated to the Cure Violence public health approach, in Los Angeles with the Gang Reduction and Youth Development strategy, and in cities in Connecticut and Massachusetts with Project Longevity and the Safe and Successful Youth Initiative, respectively.

The research also shows evidence-based strategies save money. A $1 million dollar investment in an evidence-based strategy that prevents at least three gun homicides pays for itself and more.

As of Dec. 8, Philadelphia had 335 homicides, compared with 238 on the same date in 2014 — a year when two evidence-based gun violence interventions were operational in Philadelphia: Focused Deterrence in South Philadelphia and CeaseFire/Cure Violence in North Philadelphia. At that time, homicides across the city were 41% lower. But the city phased out the strategies — one for lack of funding and one mostly for lack of will — even in light of my and my colleagues’ evaluations finding that each intervention reduced shootings by at least 30% in their target areas in the two years after the early 2013 implementation, compared to statistically matched neighborhoods not getting the interventions.

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Both strategies are based on the idea that violence is a learned behavior. Even shooters do not necessarily want to carry or use guns, but in order to stay safe, they must navigate a social terrain where the street code demands respect and disrespect is met with violence. Data are mined to carefully target the drivers of gun violence and programs are designed to change these norms just as norms around smoking cigarettes have shifted.

Using the evidence-based angle, my recommendations to the commonwealth’s new Special Council on Gun Violence include:

  1. Invest in evidence-based interventions that dismantle the norms that support shooting. Don’t fund or support programs simply because they sound good or are convenient. Cure Violence and Focused Deterrence have carefully crafted activities, trained staff, and research partners working together to faithfully implement proven strategies directly tied to reducing gun violence. The city’s planned 2020 launch of group violence intervention fits the bill. But after an initial infusion of state and local dollars for Year 1, allocation of funds must be committed annually or all careful planning efforts will be squandered.

  2. Encourage cross-agency collaboration at the state and city level that includes data sharing, enabling the integration of needed data nuanced enough to effectively target and serve those most at risk of being a shooter or being shot.

  3. Incentivize and/or fund programs to build in rigorous and transparent evaluation directly alongside program implementation. Support for research-practitioner partnerships also can help nonprofits and government agencies alike augment internal capacity for research and evaluation.

  4. Establish a state center on gun violence research that can identify policy and program options that achieved improvements in outcomes and also determine the associated costs and benefits. A cost-benefit “institute” model such as the Washington State Institute for Public Policy has been used with great success. Only proven programs with a high likelihood of large cost returns get funded.

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Philadelphia’s deep poverty, concentrated disadvantage, and structural racism are why we have such persistent violence. But those are complex, generational problems that require enormous investments to tackle over many, many years. To make progress today, we have to invest the few scarce resources we have into programs only into programs that work. We have spent too much time doing what is convenient rather than what is demonstrated. We have to make better choices.

Caterina G. Roman is an associate professor of criminal justice at Temple University.