In detective novels and television crime dramas like "CSI," the nation's morgues are staffed by highly trained medical professionals equipped with the most sophisticated tools of 21st-century science. Operating at the nexus of medicine and criminal justice, these death detectives thoroughly investigate each and every suspicious fatality. The reality, though, is far different. In a joint reporting effort, ProPublica, PBS "Frontline" and NPR spent a year looking at the nation's 2,300 coroner and medical examiner offices and found a deeply dysfunctional system that quite literally buries its mistakes. Blunders by doctors in America's morgues have put innocent people in prison cells, allowed the guilty to go free, and left some cases so muddled that prosecutors could do nothing.