There was no evidence that illegal drugs or foul play had a role in the death of the former Playboy Playmate, who collapsed on February 8 in a Florida hotel, triggering a media frenzy.
Her death also sparked a legal feud over her burial and a custody and paternity battle over her 6-month-old daughter, Dannielynn, who could one day inherit millions as the only surviving offspring of the 39-year-old widow of a billionaire.
"We are convinced, based on an extensive view of the evidence, that this case is an accidental overdose with no other criminal elements present," said Police Chief Charlie Tiger. "We found nothing to indicate any foul play."
Smith suffered severe depression after the death of her 20-year-old son, Daniel, who died of a drug overdose in September at a Bahamas hospital after Dannielynn was born, said Broward County Medical Examiner Joshua Perper.
She complained of chills when she arrived in Florida on February 5 and was later found to be running a 105 degree (40.5 Celsius) fever caused by the perforation of an abscess in her left buttock, Perper said.
"It is our determination that the cause of death is combined drug toxicity as a result of chloral hydrate and a therapeutic concentration of other medications," he said.