The lives of many Kennedys have been marked by extreme highs and lows, and Sen. Edward Kennedy was no exception. Before becoming "The Lion of the Senate," Ted Kennedy's life and career were dealt a severe blow when he drove his car off a bridge, killing 28-year-old Mary Jo Kopechne. While he was elected senator seven more times after the incident, the story's strange twists and controversial outcome remained a dark spot in Kennedy's life.

On July 18, 1969, Kennedy attended a small party on Chappaquiddick Island, near Martha's Vineyard, Mass. After 11pm, he left the party with Kophechne, a former campaign worker for his brother Bobby's presidential run, reportedly to return to their hotel rooms. After turning on a dirt road, he drove the car off a bridge into a small pond. Kennedy managed to escape, but was unable to rescue Kopechne. He returned to the party and asked two friends to help. When they were unable to free her, Kennedy swam across the channel and returned to his hotel. He did not report the accident for nearly 10 hours.

The senator denied that he was under the influence of alcohol, but pled guilty to a misdemeanor, leaving the scene of an accident, and received a two-month suspended jail sentence. The senator detailed the incident and his actions in an appeal to the people of Massachusetts:

"I made immediate and repeated efforts to save Mary Jo by diving into the strong and murky current, but succeeded only in increasing my state of utter exhaustion and alarm. My conduct and conversations during the next several hours, to the extent that I can remember them, make no sense to me at all.

Although my doctors inform me that I suffered a cerebral concussion as well as shock, I do not seek to escape responsibility for my actions by placing the blame either on the physical and emotional trauma brought on by the accident or on anyone else. I regard as indefensible that fact that I did not report the accident to the police immediately."

Watch his full 12-minute statement here.

Kennedy was re-elected to the Senate the following year, and historians have debated the tragedy's impact ever since. The Guardian writes of Kennedy's presidential ambitions:

The Chappaquiddick incident derailed any chance of Kennedy taking on Richard Nixon in 1972, when he otherwise would have ridden a wave of enthusiasm for his popular late brothers. After years of vacillation, Kennedy made what historians say was a half-hearted effort to beat Jimmy Carter for the Democratic presidential nomination in 1980. His lack of focus, along with a disastrous television interview with journalist Roger Mudd, doomed his bid as much as Chappaquiddick, historians say.

As Robert Dougherty writes in Associated Content, while Chappaquiddick has always been controversial territory, it is an especially senstitive subject now that Kennedy has died:

For Ted Kennedy's enemies, Chappaquiddick was unforgivable. For Kennedy's supporters, they forgave him for the Chappaquiddick incident, and cry out that his work in the Senate for over 40 years makes up for it. In fact, their biggest regret over Chappaquiddick is that it did stop Ted Kennedy from becoming President, and therefore saving the nation.

With Ted Kennedy now dead, the Chappaquiddick incident will now be placed in its final historical context. It has been heavily debated already for 40 years, and now the question will be how the media, and Kennedy supporters and detractors, will mention Chappaquiddick during the days of mourning ahead.

There's no denying that Kennedy worked hard to put the tragedy behind him and prove himself in the Senate in the years that followed. Presidential historian Richard Norton Smith told ABCNews.com:

"For all of us, either it would make you or break you.... Few of us experience something as soul-testing as that, but when we can weigh it against the succeeding 40 years and draw some linkage, who would believe this story would end this way, so essentially triumphant?"

The Boston Globe chronicled the night's events, including interviews with the police chief and Chappaquiddick Ferry deckhand.

— Sarah Parsons

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