Autopsy: Aubrey McClendon's death in crash accidental

OKLAHOMA CITY -- The fiery car crash in which energy industry magnate Aubrey McClendon died was an accident, the Oklahoma medical examiner's office ruled Wednesday, also noting that he had traces of a drug in his system commonly used in sleep aids.

The eight-page autopsy report shows the 56-year-old suffered numerous broken bones and other serious injuries in the March 2 crash and that his body was badly burned after he died. The report, which comes a day after police said there wasn't enough evidence to prove whether the crash was intentional, lists multiple blunt force trauma as the cause of death.

Besides traces of the antihistamine doxylamine, there were no other drugs or alcohol in his system, the report said.

The crash happened the day after the former Chesapeake Energy CEO and part-owner of the NBA's Oklahoma City Thunder was indicted by a federal grand jury for bid rigging, leading to speculation of a possible suicide.

"We spoke to anybody who may have had contact with him after he found out about the indictment," Oklahoma City Police Capt. Paco Balderrama said Tuesday. "He did not leave anything that would be interpreted as a suicide note or message."

Police have said McClendon was driving 78 mph when his SUV hit a bridge support and burst into flames and that there was no evidence suggesting he tried to avoid the crash.

The vehicle's data recorder showed McClendon was driving 88 mph and then tapped his brakes before impact, police have said. McClendon had his gas pedal floored until 1 1/2 seconds before impact, when he reduced it from 99 to 25 percent depressed, they said. Investigators found tire tracks but no skid marks.