I think the charge is appropriate, as he did not intentionally kill MJ, his negligence is still to blame. Leave drugs in the room with a drug addict and they will overdose, every doctor knows this.
Now, the more important question; Do I care that MJ died of an overdose? Nope, not in the least. He was a piece of crap freak child molester, drug addict and still 75% of the world loved him, which proves that people in general are stupid and will love anyone with fame... need more proof that people are stupid and the world is heading for hell? There is such a thing as a Snookie...