The death of a lobbyist in a Capitol Hill garage fire last month has been ruled accidental by the D.C. medical examiner's office, which said Friday that 37-year-old Ashley Turton died from burns and inhaling "products of combustion."

An autopsy also found that "acute alcohol intoxication" contributed to her death, the office said.

Turton, an energy company lobbyist, was found shortly after 5 a.m. Jan. 10 in her sport-utility vehicle, which was damaged by fire in the garage of her home in the 800 block of A Street SE, authorities said. She lived there with her husband, Daniel A. Turton, 43, the White House's deputy director of legislative affairs.

The medical examiner's office declined to elaborate on its conclusion that Turton was drunk at the time of the predawn fire. The incident remains under investigation, D.C. Fire Department spokesman Pete Piringer said.

Authorities said they are continuing to look into Turton's activities immediately before her death and studying the contents and layout of the garage and the mechanics of her 2008 BMW X-5 as they try to establish the sequence of events.

Investigators think Turton was backing out of the garage when the BMW rolled forward and struck a work bench, Piringer said.

The "low-speed" collision apparently ignited the fire, Piringer said.

Authorities have said they think Turton was striken by a medical problem or lost consciousness for some other reason as she backed up the inclined driveway.

Turton's body showed no obvious signs of trauma, authorities said. They said homicide detectives found no evidence of criminal wrongdoing in her death.

Marc S. Micozzi, a pathologist on the faculty of Georgetown University School of Medicine who is not involved in the Turton case, said in an interview that "acute" alcohol intoxication occurs when a person consumes a large amount of alcohol "very quickly, in a short time."

The incident occurred as Turton was leaving home earlier than usual for work, anticipating a busy day in her office downtown, colleagues said. That day, her employer, Progress Energy, and another North Carolina utility giant, Duke Energy, announced Duke's intention to buy Progress for $13 billion in stock.

Turton and her husband were a Washington power couple well known in Democratic circles.