The July 2, 1969 death of Brian Jones just a few weeks after he got kicked out of the Rolling Stones was officially attributed to "misadventure". The circumstances could well have contributed to that conclusion being reached. 
The guitarist was hosting what has been described as a raucous party at his place. Guests were said to have been indulging in copious quantities of alcohol and reportedly enjoying cakes with hashish baked into them.At about 9pm, the 27 year-old host's body ended-up at the bottom of the swimming pool many guests at the event had frollicked in earlier that night.
The cause of death has been questioned ever since the results of the investigation into it got announced. Many contend it wasn't an accident.
Alternate reasons for his death will be the subject of a Netflix documentary based on a book about the tragedy written by Terry Rawlings, who has uncovered a number of inconsistencies in accounts provided by witnesses at the party, including Jones' manager, who accounts claim denied he'd even been there that night for a number of years.
Whether the doc actually gets to the bottom of why Jones ended-up at the bottom of the pool remains to be seen, but it should be interesting viewing.