Every day, nearly 7,000 people die in America. And when these deaths happen suddenly, or under suspicious circumstances, we assume there will be a thorough investigation, just like we see on CSI. But the reality is very different, and the result may mean murderers go free, innocent people go to jail and public health is threatened. FRONTLINE correspondent Lowell Bergman reports the results of a joint investigation with ProPublica, NPR, and the Investigative Reporting Program at UC Berkeley. [Explore more stories on the original website for Post Mortem.]