Brooklyn Prospect Charter School is allowed to enroll some students who apply after the regular admissions deadline, a first for city charter schools.

A charter school that was actively searching for a way to admit a category of high-need students kept out by a quirk in state law has found one.

The state’s charter school law does not make provisions for schools to set aside seats for students who arrive to the city from far-flung locales after the schools’ April admissions lotteries. But Brooklyn Prospect Charter School officials wanted to be able to enroll midyear arrivals, arguing that they are precisely the kind of students that charter schools are charged with serving.

“This is a population that needs to be in a good school,” the school’s executive director, Daniel Rubenstein, said last year. “Our school — which is a small, relationship-driven, intimate environment — would be better for someone that needs a community.”

According to a memo distributed today at a meeting of SUNY’s Charter Schools Committee, SUNY’s Charter Schools Institute has approved changes to Brooklyn Prospect’s admissions policies that allow the school to accept the category of students, known in Department of Education parlance as “over the counters.”

SUNY CSI’s solution hews closely to one that lawyers for the institute first identified last year. Taking advantage of the right provided in state law to give “at-risk” students priority in admissions, the school created an at-risk category that includes only students who move to the city after April 1 and also are English language learners, from low-income families, or have a parent in the military. Applicants meeting those criteria will zoom to the top of the school’s waiting list and get the first crack at seats that open up over the summer and during the school year.

The admissions policy change will not allow Brooklyn Prospect to serve some high-need categories of over-the-counter students, including those who are returning to the system after relocating temporarily, dropping out, or being incarcerated.

The new admissions rules also come in addition to, not instead of, the school’s requirement that at least 40 percent of each entering class be filled with students who are eligible for free or reduced-price lunch. SUNY CSI approved that mandate last year, also on Brooklyn Prospect’s request.

James Merriman, CEO of the New York City Charter School Center, said the new admissions rules represented one way to get around the admissions challenge imposed by the state’s charter school law. But he said it is not the only way to improve charter schools’ capacity to serve high-need students, which they are increasingly under the gun to show they are doing.

“I think that’s just an increasing trend among charter school operators: looking at, as they get to scale and are more of a system, how do we integrate into the system and serve as broad an array of students as possible,” Merriman said.

The charter institute’s report notes that Brooklyn Prospect officials presented research that showed that children of active duty military personnel are at risk of academic failure. The school’s permanent location, which it moved into this year, is four miles from Fort Hamilton, an active military base in Brooklyn.