I find it strange that you're claiming that autopsies are not done if cause of death is not suspicious, ET.
When my Dad died, it was pretty evident how he died (he jumped from a height in BKK), but an autopsy was done on him. We didn't request it, I imagine the police did. OK, so far this goes along with your statement. What I'm wondering is why do an autopsy on someone who fell to his death & not on a road accident victim? The death was obviously caused by injuries sustained in both cases & any evidence of foul play (like drugs in the blood stream) could surely be cleared up by blood test, as you & Noodles have already said. Genuine question, as I can't see how the two cases differ.