It’s a scene familiar to any fan of film or television crime dramas: In the cold light of the city morgue, the forensic pathologist, in goggles, gloves and lab coat, investigates the cause of death. In most cases, as in fiction, such investigations take place in a purpose-built facility of chilled rooms and stainless steel gurneys that is almost sacral in its silence and sterility.

Not so in Marin County, where autopsies are routinely performed…