A U.S. district judge on Tuesday dismissed an 18-year-old special-education lawsuit against the District’s public school system, ending judicial oversight of how school administrators respond to families awaiting services for students with disabilities.

City leaders hailed Judge Paul Friedman’s decision, marking it as a vote of confidence that the city’s education reform efforts are paying off.

The decision allows the schools to administer special-education services without a court-appointed monitor routinely checking in and reviewing files to track performance.

“This is a huge day for the District and for children with disabilities,” Mayor Vincent C. Gray (D) said during a news conference at the Wilson Building after the dismissal. “Our education agencies worked tirelessly to achieve this goal.”

Gray detailed many improvements to the city’s special-education services, including more speedy delivery. He said the number of formal complaints from families has dropped significantly. He also said the number of children with disabilities who were placed in private schools at taxpayer expense — because public schools could not meet their needs — declined by 56 percent, from 2,204 to 975. That exceeds a goal Gray set early in his administration.

D.C. Schools Chancellor Kaya Henderson thanked the “teachers, paraprofessionals, special- education coordinators, psychologists, social workers, related service providers, case managers, administrators, school leaders, compliance team leaders, attorneys and special-education program staff members” for their hard work, which she said shows that the city schools should be allowed to oversee special-education services.

“We inspired enough confidence in the courts that we put the systems in place that we will never go back to the times of dysfunction and lack of services that used to characterize DCPS,” Henderson said.

Friedman dismissed the Jones portion of what is known as the Blackman-Jones case, a combination of two 1997 class-action lawsuits against D.C. Public Schools on behalf of students with disabilities. The lawsuits claimed that the school system violated federal special-education law in the way it handled administrative hearings for parents who requested 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, but nearly a decade later the schools were still out of compliance. In 2006, the school system entered into a settlement with the parents that required the city to meet three goals: Eliminate a backlog of more than 2,000 pending hearing-officer decisions and settlement agreements; make sure that at least 90 percent of such determinations and agreements are reached in a timely manner for a 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 dismissed in 2011.

A year later, a federal court released the District from oversight in a separate 1995 class-action lawsuit known as Petties v. D.C. , which related to making prompt payments to private schools and transporting students with disabilities to school safely, reliably and on time.

In a motion filed this fall, former attorney general Irvin B. Nathan wrote that the city had made steady progress in the only remaining case. As of this past summer, the city reported that more than 90 percent of 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. On Tuesday, the judge affirmed that progress.

The U.S. Department of Education, which provides special-education funding to the District, also this year noted progress in services, though the District remains a “high risk” jurisdiction by federal standards.

Officials with the Office of the State Superintendent of Education said that for the first time in the city’s history, it has made enough progress to be removed from tighter federal control in two areas: timeliness of hearing-officer determinations and of transitioning young children into early special-education services.

The federal government is still monitoring some other areas, including the timeliness of the city’s initial and subsequent evaluations, as well as compliance with a requirement to develop transition plans for special-education students who are preparing for life beyond high school.

“The District was at 0 percent compliance in 2008, and now we are at 73 percent compliant,” said Amy Maisterra, assistant superintendent for elementary, secondary and specialized education for OSSE. “We have seen really good improvement. They want to see us at closer to 100 percent.”