The District of Columbia is asking a U.S. District Court judge to dismiss an 18-year-old special education lawsuit and end judicial oversight of how it responds to families awaiting services.

The motion, filed Friday by Attorney General Irvin B. Nathan, says that the system has improved significantly and the city is ready to resume full control of the administration of its program.

“The historic deficiencies that led to this litigation have been eliminated,” the motion says.

The motion came in the Blackman-Jones case, a combination of two class-action lawsuits brought by parents of students with disabilities against D.C. Public Schools in 1997. The lawsuits claimed that the schools violated federal special education law.

The cases deal with administrative hearings that parents requested in efforts to secure adequate services for their children.

In the Blackman case, parents said that due process hearings were not scheduled and decisions were not issued in a timely way. In the Jones case, parents said that once a settlement agreement was reached, the school system did not provide the services requested.

The judge ruled in favor of the parents. Nearly a decade later, when the schools were still out of compliance, they entered into a settlement with the parents that required the city to meet three goals: Eliminate a backlog of cases that had reached 2,251 pending hearing officer decisions and settlement agreements as of 2006; make sure that at least 90 percent of such determinations and agreements are reached in a timely manner for a full 12-month period; and have no cases more than 90 days overdue for implementation of services.

A court-appointed monitor tracked the city’s progress and two years later, the first requirement was met when the backlog was eliminated. The Blackman part of the case was later dismissed.

The city has made steady progress during the past eight years on the two remaining requirements, the motion says.

As of June 30, 91.9 percent of the hearing officer decisions and settlement agreements had been implemented in a timely way during the preceding year, and no cases were more than 90 days overdue for implementation, according to the city.

The motion describes a new database the school system developed to monitor its pending cases in a more consistent and reliable way. In the previous system, it says, “compliance reports were compiled manually by an external contractor using numerous Excel spreadsheets.”

U.S. District Judge Paul L. Friedman in 2012 dismissed another long-running case, Petties v. District of Columbia, that dealt in part with inadequate transportation services for special education students.

After years of court oversight, the school district improved its services to the point that students were reliably getting to school on time, and the case was dismissed.