The researchers looked at parts of New York that had many stops, not necessarily because those places had high crime or other correlated factors, but because they happened to be assigned a precinct commander who was more likely to advocate frequent stops. Within these neighborhoods, students may not have been stopped themselves. But they went to school in communities where this kind of policing was pervasive.

The negative effects on education appeared for girls, too, even though they were far less likely to be stopped by police than boys or young men. That implies, the researchers suggest, that something deeply embedded in the girls’ environment — like fear or distrust of authority that students learned from it — might have hindered their education. More police stops, the researchers found, were also associated with chronic absenteeism.

That study adds to other research in New York finding that black male students who were more exposed to stop-and-frisk had lower test scores. And other research using surveys about experiences with the police has found that students around the country who were arrested or stopped, or who witnessed these encounters or knew of others involved, had worse grades.

That these effects appear strongest for black students suggests that aggressive policing could worsen racial achievement gaps in school as well.

“All these kinds of disadvantages can accrue and build up,” said Aaron Gottlieb, a professor at the Jane Addams College of Social Work at the University of Illinois at Chicago, who has studied policing and student grades. “Let’s say a police stop reduces the likelihood that you go to college. That’s going to impact your earnings in the long run.”

Other research shows that negative interactions with the police can shape how residents think about government and civic institutions, and even democracy more broadly.

“It teaches something really important — and something really negative — about what agents of the state and bureaucracies are supposed to be doing in your community, what role they play, what their character is,” said Amy Lerman, a political scientist at the University of California, Berkeley.