The Guardian/Observer has an excellent summary of the story of Dr. Nick, the personal physician of Elvis Presley. According to Wikipedia, Dr. George Constantine Nichopoulos was indicted in 1980 on 14 counts of overprescribing drugs to Elvis Presley and Jerry Lee Lewis, as well as twelve other patients, and ultimately the doctor lost his license to practice medicine.
The ABA Journal has an article on how attorney James Neal successfully defended Dr. Nick before a Memphis jury.
One point of comparison between Dr. Nick and Dr. Murray: Dr. Nick tried to keep Elvis's addiction to prescription drugs in check, going so far as to "persuade Knoll, the manufacturers of Dilaudid, Elvis's favourite painkiller, to press a special batch of a thousand pills without any active ingredients. It took a year of letter-writing and legal wrangling. But they looked just like the real thing. They cost him $5.98 apiece."