An 84-year-old woman patient at St. Elizabeths Hospital, who was there because she needed a supervised environment, was stomped to death yesterday in her dormitory.

D.C. police said they charged a fellow patient, Dennis Michael Wilson, 19, with homicide in the woman's death.

Investigators said the killing came after the suspect had asked how he could be transferred to a section of the hospital used to treat the cirminally insane.

The victim, Mary Braxton, had been a patient at St. Elizabeths, a mental hospital in Southeast Washington, for many years. She died at 2:20 p.m. from blunt force blows on the head and neck. "She was literally stomped to death," a D.C. homicide detective said.

There have been several incidents in recent years in which patients at the hospital have been charged with violent crimes against fellow patients.

Wilson and the dead woman, were both living on the third floor of the Edith M. Haydon pavillion. Hospital officials had once used the building for geriatric patients, but in recent years integrated it with people of varying ages in an attempt to create a more normal atmosphere.

According to police, Wilson, who had admitted himself voluntarily to the hospital last July, asked a supervisor yesterday morning how he could be transferred to the John Howard Pavillion, the hospital's maximum security building for the criminally insane.

The supervisor, police said, told Wilson that he did now want to go to that building because it housed violent persons and he was not violent.

Investigators speculated that Wilson may have sought the transfer in the belief that the food was better at the Howard pavillion.

About a half hour after discussing the transfer question with the supervisor, polic said, Wilson returned and told the supervisor that Braxton was on the floor of a nearby room.

Attendants found her unconscious and she died shortly afterward in the hospital's medical center, authorities said.

Wilson was beind held last night in the central cell block of D.C. police headquarters.

Last May a 59-year-old St. Elizabeths patient died of injuries and ensuing complications after a struggle with hospital workers. Hospital officials said the patient had become combative.

In September of last year a 66-year-old patient at the hospital was found fatally beaten in a locked seclusion room. Four months earlier a 92-year-old woman was raped in her ward, and a 19-year-old man was charged.

Other deaths in recent years have caused the hospital staff to say that they are re-evaluating their practice of mixing patients of varying ages. The hospital spokesman Harold Thomas, was not available for comment last night.