In an unexpected move, the District government has decided to challenge a D.C. Superior Court judge's order that the city carry out sweeping reforms at its two institutions for juvenile offenders.

The order, by Judge Gladys Kessler, followed months of negotiations between city lawyers and attorneys from the Public Defender Service who participated in a lengthy inquiry into conditions at Cedar Knoll and Oak Hill, which are known jointly as the Children's Center.

Kessler's order is directed at the city's Department of Human Resources. In court papers filed later Thursday, however, the city argued that Kessler had no legal grounds for issuing the order, which directed the department to draw up plans for specific changes at the Children's Center and set deadlines for submission of the plans to the court.

Even if Kessler had the power to order the changes, the city argued, the order is invalid because there was no evidence that the rights of the children are being violated at the two institutions.

Specifically, the D.C. Corporation Counsel's office, acting for the department, asking Kessler to postpone implementation of her order until the city can take its case to the D.C. Court of Appeals. The Public Defender Service was appointed by Kessler to represent the interests of the children.

Kessler's 18-page order, released earlier this month, calls for improved medical and psychiatric care, tighter controls over distribution of medication, improved job training for employes and orders the city to submit a plan to remedy what she described as "critical staffing-level inadequacies."

The order also provides for a confidential system for children to notify authorities of instances in which they feel they have been abused or mistreated by staff members.

The city expressed some concern early in the inquiry over Kessler's authority to take such actions, but the issue was not pursued in her court.

Sources have indicated that the city now feels it does not have the resources to make the broad range of changes included in Kessler's order such as hiring new staff and remodeling of some of the facilities.

In addition, some officials contend that Kessler's action was an unwarranted intrusion of the court into the operations of the Department of Human Resources.

In the court papers, the city asserted that the notice of its intent to appeal does not mean it would not carry out some of the changes addressed in Kessler's order.

Rather, the city said, it sees many of the changes as "desirable" and will voluntarily implement those changes where "administratively and budgetarily possible."

The Department of Human Resources operates both Oak Hill, a maximum security facility, and Cedar Knoll, a medium security institution that it also used to house youths awaiting trial.