Interesting stuff from Wikipedia... perhaps it wasn't a suicide after all...
On June 4, 2009, Carradine was found dead in his room at the Swissôtel Nai Lert Park Hotel on Wireless Road, near Sukhumvit, in central Bangkok, Thailand. A police official said Carradine was found hanging by a rope in the room's closet, and the Bangkok Post reported that his body was found curled up in the wardrobe with a shoelace tied around his genitals and neck.
Khunying Pornthip Rojanasunand, a Thai forensic pathologist and Director of Central Institute of Forensic Science, stated the incident met four of the criteria for accidental death involving autoerotic asphyxiation. Police Lieutenant General Worapong Chewprecha, Commander of the Metropolitan Police, remarked that the closed circuit television installed within the hotel supported the theory that no other persons were involved with the death. Carradine's representative and family members told the press that they believed the death to be accidental and not a suicide. However it has also been reported that Carradine was found "with his hands tied behind his back." Chuck Binder, Carradine's manager, indicated neither suicide nor accident was the likely cause since "the family has been told Carradine's hands were immobilized (behind his back) by the rope."
Carradine was in Bangkok to shoot his latest movie, Stretch, and had been known to join the film crew for dinner. The crew noticed his absence when going out to dinner on June 3, but assumed he was simply taking the night off.