That claim is not just speculative. Over the past two decades, gentrification has become a norm in major American cities. The typical example is a formerly low-income neighborhood where longtime residents and businesses are displaced by white-collar workers and overpriced coffeehouses. But the conventional wisdom that image reflects—that gentrification is a result of an economic restructuring—often leaves out a critical side effect that disproportionately affects communities of color: criminalization.

When low-income neighborhoods see an influx of higher-income residents, social dynamics and expectations change. One of those expectations has to do with the perception of safety and public order, and the role of the state in providing it. The theory goes that as demographics shift, activity that was previously considered normal becomes suspicious, and newcomers—many of whom are white—are more inclined to get law enforcement involved. Loitering, people hanging out in the street, and noise violations often get reported, especially in racially diverse neighborhoods.

“There’s some evidence that 311 and 911 calls are increasing in gentrifying areas,” Harvard sociology professor Robert Sampson told me. And “that makes for a potentially explosive atmosphere with regard to the police,” he added.

By degrees, long-term residents begin to find themselves tangled up in the criminal-justice system for so-called “quality of life” crimes as 311 and 911 calls draw police to neighborhoods where they didn’t necessarily enforce nuisance laws before. As Paul Butler, a former federal prosecutor in Washington, D.C., describes it, misdemeanor arrests are more reflective of police presence than the total number of infractions committed in an area. “It’s not a question of how many people are committing the crime—it’s a question of where the police are directing their law-enforcement resources,” Butler said. “Because wherever they direct the resources, they can find the crime.”

In 2013, the city of San Francisco launched Open311, a mobile app that allows residents to easily report public disorder like loitering, dirty sidewalks, or vandalism by snapping a photo and sending their location. The app can feel altruistic; residents, for example, are able to report the whereabouts of homeless people who seem to be in need of assistance. But some worry that the dispatches can result in unnecessary citations or harassment. And while broken-windows policing remains controversial, a 2015 poll suggested that it’s still largely accepted by the general public, so when people see something, they’re likely to say something. After the app launched, 311 calls increased throughout the city, and one study showed that gentrifying neighborhoods saw a disproportionate spike.

Butler, who recently wrote the book Chokehold: Policing Black Men, believes that this is a result of newcomers refusing to assimilate to longstanding neighborhood norms. “Culturally, I think the way that a lot of African American and Latino people experience gentrification is as a form of colonization,” he said. “The gentrifiers are not wanting to share—they’re wanting to take over.” One of the tools they can use to take over public spaces, he argues, is law enforcement.