A South Carolina grand jury is scheduled to convene today to consider indictments in the slaying of C. Daniel Swansen, a 52-year-old Fairfax real estate developer whose body was found wrapped in a bedspread and bound with wire in the back of his vacation camper last fall.

South Carolina authorities have charged three persons with murder in the Sept. 27 slaying of Swansen, who they believe was shot once in the back of the head with a .357 magnum pistol as he lay in the camper bed near Manning, S.C., police say.

The three, described by police as hitchhikers whom Swansen picked up, are Richard C. Johnson, 22, of Morehead City, N.C., described by authorities as an ex-convict; Connie Hess, 17, of Omaha, whose father says she is a teen-aged runaway, and Curtis Harbert, 20, of Moorefield, W.Va.

They are being held without bond in the related shooting death of a South Carolina highway patrolman, whose body was found in roadside grass near Swansen's camper several hours after the Swansen killing is believed to have taken place, police say.

If suspects are indicted, the earliest they would go to trial is March, said Wade Kolb, a South Carolina prosecutor.

Swansen, who was married and a father of three, was a successful Northern Virginia businessman whose behavior was sometimes erratic and who had become increasingly depressed over the death of a son several years earlier, according to friends and relatives.

He spent the last hours of his life driving the camper south and partying in the company of hitchhikers he had picked up along the way, authorities have said.