Dr. Averette Parker, chief for the last year of the District's much-criticized Mental Health Services Administration, resigned this week amid a new effort by city officials to resolve the long-running court fight over the quality of the city's community mental health care.

Parker, a psychiatrist, submitted her resignation Thursday, according to Dr. Ernest Hardaway, the D.C. public health commissioner. She asked to be reassigned to one of the city's mental health clinics, a request Hardaway said he would honor. He said no date has been set for her transfer and that he has not picked her successor.

Hardaway said Parker was not forced to resign, but acknowledged that "we've had some philosophical differences."

Hardaway said he wanted "a more collaborative relationship" with the Mental Health Law Project, the advocacy group that since 1978 has pressed St. Elizabeths Hospital to release as many patients as possible to community care facilities. The group has regularly attacked the city for its failure to provide the services necessary to accommodate the increased number of patients released.

Parker said that while she has had some differences with Hardaway, she is mainly resigning because of "other responsibilities," a desire to spend more time with her teen-age daughter and to pay more attention to her private psychiatric practice.

She said that whoever is selected as her successor will have to make a substantial commitment in time and effort toward carrying out the deinstitutionalization, which affects more than 2,400 patients who are treated or hospitalized at St. Elizabeths and could be cared for in less restrictive settings in the city.

"I think it's going to be forever with us, until the federal mental health programs at St. Elizabeths and the city mental health programs are merged," she said. "The advocates are always going to be dissatisfied with something."

The law project has asked U.S. District Judge Aubrey E. Robinson Jr. to appoint a special master to oversee the deinstitutionalization, and to function in effect as a boss over the city's mental health administrators and programs.

But Hardaway said that "our commitment is that we are going to provide the resources" to improve the city's mental health care. He said that in the last 10 days he has met twice with representatives of the law project to develop "a working relationship."

"I think you'll find a different attitude," he said, "and that will be transmitted to the court."

Norman Rosenberg, director of the law project, said, "We are happy the attitudinal change is there. We are justifiably skeptical about this new approach until we see some kind of delivery" of new services.

He said it is "not clear that the dollars will be there to fulfill the programs that we feel are essential."