Rafael A. Mangual is a fellow and deputy director of legal policy at the Manhattan Institute for Policy Research and a contributing editor of City Journal.

Our history illustrates that, at their noblest, peaceful protests can inspire meaningful change. The terrible injustice suffered by George Floyd sparked a spontaneous movement meant to diminish racial disparities, and peaceful demonstrators have an opportunity to advance that cause. But in the places where protests descended into looting, arson and violence, the result could be the opposite. As cities try to recover in the weeks and months ahead, they should focus on how to mitigate the negative effects of lawlessness on economic opportunity and public safety, which could end up exacerbating two of the biggest challenges facing black and brown neighborhoods in and around America’s cities.

On the economic front, history offers some clues about the scars the unrest may leave behind. While the nationwide riots of the 1960s and the Los Angeles riots in 1992 were much larger in scope than the recent violence, analyses of their economic impact suggest that it could take years for some communities to bounce back. A 2007 study published in the Journal of Economic History, for example, found that the riots of the 1960s led to significant population loss and “depressed the median value of black-owned property between 1960 and 1970, with little or no rebound in the 1970s.” More recently, a 2004 report in Urban Studies found that the 1992 Rodney King riots resulted in “a cumulative loss of at least $3.8 billion in taxable sales and over $125 million in direct sales tax revenue” for Los Angeles. And images of boarded-up businesses destroyed in Ferguson, Mo., remind us that the city still hasn’t recovered from the disturbances of 2014.

The economic damage may be compounded by an erosion of public safety. The broken windows theory of policing recognizes the link between visible disorder and serious crime: Much as one broken window left unrepaired may lead to the destruction of others — because it sends the message that no one will intervene to fix them — so, too, does ignoring lower-level offenses committed in public spaces ultimately invite more serious criminality. When people look around their neighborhoods and see vagrancy and defaced property, they understandably retreat in fear — emboldening gangs, drug dealers, thieves and other serious criminals to move in.

Most of the demonstrators protesting George Floyd’s death have been peaceful, especially over the past few days. But many of the lasting mental images of the recent violence — and the literal broken windows, graffitied monuments, burned-out buildings and looted storefronts left in their wake — could contribute to a heightened sense of fear for some living in affected communities. The scars of public disorder are widespread, and people have retreated from public spaces. Broken windows theory, as well as the research on the link between the built environment and crime, suggests that, without swift efforts to restore normalcy, an increase in criminal activity may not be far off.

This is especially true if the police pull back — as some of the protesters pushing to “defund the police” now advocate. Recent research and past experience suggest law enforcement might retreat regardless. After protests wracked Chicago in 2015 following the death of Laquan McDonald, city policing became much less aggressive. The consequences were captured in a study published in the University of Illinois Law Review showing that a sharp drop in pedestrian stops was “the likely cause” of 245 additional homicides that year, concentrated in minority neighborhoods. A similar decline in enforcement by Baltimore police after the Freddie Gray protests has been followed by a dramatic rise in annual homicides, with Charm City experiencing a record-high homicide rate in 2019.

Rather than entertain calls to defund the police, cities should be considering more practical approaches to mitigating these effects. And their efforts should be targeted. Central business districts are more likely to have access to the resources needed to rebound; city leaders must do their best to ensure that the more modest, largely minority neighborhoods affected — in Minneapolis, Philadelphia, St. Louis, Chicago, Louisville, Atlanta and other cities — are not left behind.

The best way to start is by making the physical environments in damaged communities less vulnerable to more serious crime. Recent research by University of Pennsylvania criminologist John MacDonald shows that by abating vacant lots and making productive use of abandoned properties, cities can help mitigate the conditions that lead to crime — which suggests that municipalities and philanthropic groups should literally clean up the mess, and quickly.

For their part, police leaders must redouble their efforts to ensure that officers follow the training and protocols that could have prevented the deaths of George Floyd, Laquan McDonald and Freddie Gray, and take swifter action to hold accountable those found to have abused their power. But they must simultaneously do all they can to boost the morale of officers in their commands and remind them of the public support — overshadowed in recent days by the chaos — they still rightly enjoy.

It would be tragic if the aftermath of George Floyd’s death worsened conditions in America’s urban minority neighborhoods. Getting these solutions right is our best hope of avoiding the bleak outcomes that have followed earlier episodes of civil unrest.

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