The investigation into Chappaquiddick was cloaked in an atmosphere of threats, fear and intimidation. The attempt to have Mary Jo Kopechne’s body exhumed for an autopsy was fought by her parents — and would become their lasting regret. Hear from the experts who testified about Mary Jo’s final moments - and from the last man who tried to find out what happened that night. To continue the discussion, join our Facebook group to share your thoughts and theories or reach us directly at [email protected]. And for more on the case, go to people.com/coverup.Learn more about your ad choices. Visit megaphone.fm/adchoices