Here is video of the speech Sen. Ted Kennedy made to try and rehabilitate himself following the death of Mary Jo Kopechne on Chappaquiddick Island after he drove her off a bridge in his car, leaving her to drown on July 19, 1969. Tomorrow will be 40 years since it happened. In this video, he says he finds his own behavior "indefensible" in waiting for hours to call authorities after getting out of the car himself, but leaving Kopechne in the car. Obviously, the entire speech was his attempt to indirectly defend himself. Below is a summary of "The Chappaquiddick Incident," as it came to be called, by Larry Sabato:
On the evening of July 19, 1969, Sen. Edward M. Kennedy of Massachusetts drove his Oldsmobile off a wooden bridge on Chappaquiddick Island, drowning his passenger, a young campaign worker named Mary Jo Kopechne. The senator left the scene of the accident, did not report it to the police for many hours, and according to some accounts considered concocting an alibi for himself in the interim.
At the time, Kennedy managed to escape severe legal and political consequences for his actions thanks to his family's connections (which helped to contain the inquest and grand jury) and to a nationally televised "Checkers"-like speech broadcast a week after the accident. But virtually no journalist who has closely examined the evidence fully believes Kennedy's story, and almost 30 years later, the tragedy still trails the senator, with aggressive press investigations revived in five-year anniversary intervals.
Probably more than any other single factor, Chappaquiddick – a frenzy without end – has ensured that Ted Kennedy would not follow his brother John to the White House.
NOTE: Here is a Time Magazine article from May 11, 1970, which goes into great detail about the incident.