In truth, the good doctor shouldn't have served minute one. It's time society stops taking a pound of flesh.
I'll take the other side, and argue that a medical doctor is bound by his oath, and to administer drugs in the manner he did, violates that oath, and is grossly negligent.
The sentence was light, considering a person died because of his negligence. And those who might argue that Jackson had it coming, because he was so screwed up--I'll counter no, those are the ones MOST in need of professional doctors' care.