A new report points to charter schools as a potential avenue for fighting school segregation, but cautions that New York State law could make promoting diversity difficult in the Empire State.

In theory, charter schools are well positioned to achieve racial integration because they do not admit students based on their home address, writes researcher Halley Potter in “Charters Without Borders.” That makes them more like magnet schools, which can enroll students from all over a city, than like many elementary and middle schools in New York City, which admit students based on where they live.

But in New York, where state law requires charter schools to fill seats with students who live within the local district before offering seats to those who live outside it, that benefit is limited. New York is one of seven states with such a law.

New York City’s 32 school districts include some with racially and socioeconomically diverse populations. But many, including in parts of the Bronx and Brooklyn where the charter sector is strongest, do not have many residents who are white or middle-class.

Potter argues that the state’s enrollment rules limit chances to mix students of different backgrounds, which she said results in students attending racially isolated charter schools.

“It’s such a missed opportunity to restrict charter schools to in-district enrollment,” said Potter, who is a fellow at The Century Foundation and co-author of “A Smarter Charter: Finding What Works for Charter Schools and Public Education.” “If this were allowed for charter schools it would be a huge tool.”

The report comes as segregation in New York City schools is attracting more attention. A UCLA report issued last year found that New York Schools are among the most segregated in the country. The same report found that in the Bronx, Brooklyn, and Manhattan, nearly all charter schools were intensely segregated in 2010, with less than 10 percent white enrollment. The mayor and schools chancellor responded to a recent Chalkbeat story about stalled school diversity plans. The state has offered millions in new grants to city school districts and individual schools with plans to boost their diversity.

In crucial ways, racial segregation in charter schools stems not only from the letter of New York’s law, but from its spirit, too.

Some states permit charter schools simply as alternatives to local schools, opening them to middle-class families that prefer a different instructional approach or a focus on the arts, for example. In New York, the schools were created specifically to offer options to families whose children would otherwise be required to attend low-performing neighborhood schools.

That ethos has led charter operators to focus on enrolling local students, rather than engineering diverse student bodies.

“Our belief is that every community deserves great schools,” said Eve Colavito, the head of school for DREAM Charter School in East Harlem. “We do everything in our power to make sure that our scholars are from the surrounding neighborhoods.”

Potter said Colavito’s approach should not be treated as the only way forward.

“The public narrative around charter schools focuses on one particular kind of school,” Potter said. “That doesn’t take into account that some charter schools use their flexibility precisely to integrate.”

Indeed, some city charter operators have sought to use charter school enrollment rules, which require that students be admitted by lottery, to achieve diverse student populations. They include Daniel Kikuji Rubinstein, who runs Brooklyn Prospect Charter School and helped start the National Coalition of Diverse Charter Schools, as well as Success Academy CEO Eva Moskowitz, who argued in an op-ed earlier this month that charter school admissions lotteries could be used as tools to create diverse schools.

But New York City charter schools that enroll diverse populations are in racially and socioeconomically diverse districts. Moskowitz pointed to her schools on the Upper West Side and in Brooklyn’s Cobble Hill as evidence that residential diversity can translate into school diversity, but she did not note that her network’s Bronx and eastern Brooklyn schools are far less diverse.

James Merriman, CEO of the New York City Charter School Center, said charter operators chose early on to employ strategies other than integration to boost students’ skills.

The attitude was: “I’m not going to spend a lot of time trying to persuade white folks to go to school with black folks … I’m going to do what I can control,” Merriman said.

Though Merriman and Potter both believe charter schools can help foster school diversity, neither said they are the sole solution to school segregation.

“I don’t think [charter schools are] uniquely qualified,” Merriman said. “I think they are one part of the answer.”