Success Academy officials violated civil rights laws when changing students’ special education services according to a complaint filed Thursday, resulting in some students suddenly changing classrooms and losing months of required instruction.

The complaint, filed with the state’s education department, alleges a pattern of school officials unilaterally changing special education placements without holding meetings with parents, moving students to lower grade levels, and even ignoring hearing officers’ rulings. In some cases, students were removed from classrooms that integrate special and general education students and sent to classrooms that only serve students with disabilities.

Filed by the advocacy group Advocates for Children and a private law firm, the complaint says that Success Academy officials often force parents to fight the charter network in federal court to maintain the services that are listed on a student’s individual learning plan, also known as an IEP.

“Students with disabilities do not give up their civil rights when they enter a charter school,” Kim Sweet, executive director of Advocates for Children, wrote in a statement.

The city’s education department, also named in the complaint, is responsible for making sure students in charter schools receive the services laid out on their learning plans, and setting up meetings with parents to discuss any changes. But, according to the complaint, the education department “has no system to ensure that these schools comply” with those rules.

With 17,000 students, Success Academy is New York City’s largest charter operator and has previously been accused of denying services to students with disabilities, and even pushing them out of their schools. In 2015, at least one school was found to have a “got to go” list of students that school leaders wanted to see leave. More recently, the network filed a lawsuit claiming the opposite is true: Success officials said they often fight for services for students with disabilities, only for the requests to be denied or delayed by the city.

“This is really about the fact that some parents and Advocates for Children believe that there should be different standards for promoting students with special needs,” Success spokeswoman Anne Michaud wrote in a statement. “That is not law nor should it be.”

The complaint includes five student examples across four Success Academy schools. In one case, a 13-year-old student at Success Academy Harlem East was suddenly moved from a 7th grade classroom that included a mix of typical students and students with disabilities into a smaller 6th grade classroom reserved for students with learning differences. The student was being taught material she had already covered.

The city never held a required meeting to discuss the changes with the student’s mother, a requirement under federal and state law, and the charter network insisted the change was final, according to the complaint. Parents are allowed to challenge those decisions by demanding an administrative hearing, and in the meantime, a hearing officer ordered the charter network to reinstate the student in her original classroom.

But as in other cases, Success officials disputed that “pendency” order, according to the complaint, and the student wound up missing seven months of 7th grade instruction (the student was later moved to a 6th grade classroom that included general education students). In other cases, families were eventually forced to file federal complaints to restore services the student was originally promised. (Chalkbeat has previously reported that students at the network’s high school have been sent back a grade mid-year.)

“As a result of this lengthened process of first obtaining the pendency order at an impartial hearing and then needing to enforce the order in federal court, students with disabilities are losing ordered instruction time, solely because they attend a charter school,” according to the complaint. Three of the five students included in the complaint are no longer at Success Academy.

For its part, Success defended its handling of special education placements. “While some parents find it painful to have a child held back, it is not in these children’s interest just to pass them along when they haven’t mastered the necessary material,” Michaud said in the statement.

The complaint calls on the state education department to force Success Academy to come up with a plan to comply with rules governing students with disabilities, and for the city’s education department to “develop an accountability structure” that would boost oversight of charter school compliance with federal and state laws governing students with disabilities.

City and state education officials said they are reviewing the complaint. A spokesman for the city’s education department wrote in an email that “The practices described in the complaint are contrary to DOE policy.”

A spokeswoman for SUNY, which is Success Academy’s authorizer, did not respond to a request for comment.