Was Elvis' death murder?
No, I don't think so.

And I think the two deaths are very, very similar: The entourages and the MD knew, and chose to do nothing. Or tried to do something and were rebuffed or fired. Both "stars" preferred to surround themselves w/ "yes men" or by individuals who took advantage of them--but also did their "dirty" work (so to speak).

MJ and Elvis had to have known that the medications were potentially fatal. They weren't stupid.
To me, it's almost like they chose to play russian roullette every time they took the pills, or got an injection. It was a risk they were willing to take for whatever reason.

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Mental that one, I'm telling you. ---Ron Weasley, "Harry Potter and the Chamber of Secrets"