The multi-layered causes of crime

Most theories for the great crime decline that swept across nearly every major American city over the last 25 years have focused on the would-be criminals.

Their lives changed in many ways starting in the 1990s: Strict new policing tactics kept closer watch on them. Mass incarceration locked them up in growing numbers. The crack epidemic that ensnared many began to recede. Even the more unorthodox theories — around the rise of abortion, the reduction in lead or the spread of A.D.H.D. medication — have argued that larger shifts in society altered the behavior (and existence) of potential criminals.

But none of these explanations have paid much attention to the communities where violence plummeted the most. New research suggests that people there were working hard, with little credit, to address the problem themselves.

Local nonprofit groups that responded to the violence by cleaning streets, building playgrounds, mentoring children and employing young men had a real effect on the crime rate. That’s what Patrick Sharkey, a sociologist at New York University, argues in a new study and a forthcoming book. Mr. Sharkey doesn’t contend that community groups alone drove the national decline in crime, but rather that their impact is a major missing piece.

“This was a part that has been completely overlooked and ignored in national debates over the crime drop,” he said. “But I think it’s fundamental to what happened.”

Between the early 1990s and 2015, the homicide rate in America fell by half. Rates of robbery, assault and theft tumbled in tandem. In New York, Washington and San Diego, murders dropped by more than 75 percent. Although violence has increased over the last two years in some cities, including Chicago and Baltimore, even those places remain safer than they were 25 years ago. And crime has continued to fall in other cities, most notably New York, where shootings are at a record low.

This long-term trend has fundamentally altered city life. It has transformed fear-inducing parks and subways into vibrant public spaces. It has lured wealthier whites back into cities. It has raised the life expectancies of black men. And even in an age of widening urban inequality, it has meant that the daily lives of the most disadvantaged are less dangerous now than they were a generation ago. These poor neighborhoods, Mr. Sharkey has found, have been the greatest beneficiaries of this tectonic change in safety.

The same communities were participating in another big shift that started in the 1990s: The number of nonprofits began to rise sharply across the country, particularly those addressing neighborhood and youth development.

Mr. Sharkey and the doctoral students Gerard Torrats-Espinosa and Delaram Takyar used data from the National Center for Charitable Statistics to track the rise of nonprofits in 264 cities across more than 20 years. Nonprofits were more likely to form in the communities with the gravest problems. But they also sprang up for reasons that had little to do with local crime trends, such as an expansion in philanthropic funding. A spike in nonprofits addressing subjects like the arts and medical research occurred in this same era.

Comparing the growth of other kinds of nonprofits, the researchers believe they were able to identify the causal effect of these community groups: Every 10 additional organizations in a city with 100,000 residents, they estimate, led to a 9 percent drop in the murder rate and a 6 percent drop in violent crime.

In a criminology field that has produced some eyebrow-raising ideas, this one is actually not so surprising. That national finding echoes local studies of some individual programs, like one run by the Pennsylvania Horticultural Society that converts abandoned lots into green spaces and that has been linked in Philadelphia to reduced gun violence.

The research also affirms some of the tenets of community policing: that neighborhoods are vital to policing themselves, and that they can address the complex roots of violence in ways that fall beyond traditional police work.

“It’s absolutely consistent with what I would argue is probably the prevalent theory of policing among the major cities today,” Richard Myers, the executive director of the Major Cities Chiefs Association, said of the new research.

Local organizations also say Mr. Sharkey’s results validate what they have already witnessed.

“Any time people’s basic needs are met, violence goes down — that’s not new,” said Noreen McClendon, who directs the nonprofit Concerned Citizens of South Central Los Angeles.

The group, led by Ms. McClendon’s mother for many years, was formed in the 1980s to fight a proposed waste incinerator in the neighborhood. It evolved in the 1990s to address many of the neighborhood’s other challenges. The group created dozens of block clubs to care for individual streets. It cleaned alleys and repaired potholes, and hired local ex-offenders to do that work. It established a credit union, sponsored a jazz festival and developed hundreds of units of affordable housing.

During a time of major disinvestment in cities, and severe cuts in federal support for urban programs, residents of the neighborhood believed no one else was coming to help. “Nobody,” Ms. McClendon said. And if the group had not done this work itself? “There would have been a lot more death,” she said, “between violence amongst people, violence from police brutality, just drugs.”

Many similar groups did not explicitly think of what they were doing as violence prevention. But in creating playgrounds, they enabled parents to better monitor their children. In connecting neighbors, they improved the capacity of residents to control their streets. In forming after-school programs, they offered alternatives to crime.

In the East Lake neighborhood of Atlanta, the crime rate in the mid 1990s was 18 times the national average. The drug market in the neighborhood was estimated to be doing $35 million in business a year. There hadn’t been a new building permit issued in the neighborhood in nearly three decades, a sign of how little anyone had invested in the community other than to buy drugs there.

Then the newly formed East Lake Foundation developed new mixed-income housing to replace a decaying public housing project. It started a golf program for neighborhood children on a nearby but long-deteriorating golf course. The foundation eventually opened a charter school, where the first class of seniors had a 100 percent graduation rate in May.

“We knew we wanted to see violence and crime go down in the community,” said Carol Naughton, who led the foundation for years and today is the president of a national group, Purpose Built Communities, that is trying to teach East Lake’s model in other cities. “But we’ve never had a crime-prevention program.”

Today violent crime in East Lake is down 90 percent from 1995. But Ms. Naughton is momentarily perplexed by the question of whether she believes groups like hers have gotten enough credit for contributing to that outcome.

“We’re not part of the crime-reduction world, or the public safety world, in the same way that we’re part of the health and education and housing world,” she said. “It never occurred to us that we’re not getting the credit, because we don’t even know that world is out there.”

The lesson in that response, and in Mr. Sharkey’s work — that effective crime prevention doesn’t necessarily look like stop-and-frisk, or hot-spot policing, or mass incarceration — is particularly relevant today as cities rethink policing.

“A lot of these communities were in despair because they needed resources,” said Robert Sampson, a sociologist at Harvard who has studied Chicago neighborhoods damaged by violence. “And what did they get? Well, they mainly got crime control. They got increases in incarceration.”

Those tactics may have contributed to the decline in crime as well. But they’ve come with costs that have become clearer over time, in antagonizing communities and disrupting families.

Mr. Sharkey is pointing to one possible solution with less evident downsides. And he’s suggesting that communities can effectively take on the very roles that the police say have strained them as they’ve increasingly been asked to perform jobs they weren’t trained for, as guidance counselors or marriage therapists or substance-abuse experts.

“They are taking that burden away from the police that probably never should have been there, but by default has kind of landed there,” said Mr. Myers of the chiefs association, who is also a former longtime police chief himself, in Michigan, Virginia, Colorado and elsewhere.

As Mr. Sharkey publishes his findings, crime rates are now diverging after a generation in which violence fell reliably year after year nearly everywhere. It’s not clear yet whether the great crime decline he writes about will continue. But he argues that it’s time for a new model of violence prevention, one that relies more heavily on the kind of work that these community groups have been quietly doing than on the aggressive police tactics and tough sentencing that the Trump administration now advocates.

“The model that we’ve relied on to control violence for a long time has broken down,” Mr. Sharkey said. If communities want police to step back, he is pointing to some of the people who can step in. “This gives us a model. It gives us another set of actors who can play a larger role.”