On the night of July 18, 1969, Kennedy was on Martha's Vineyard
's Chappaquiddick Island
at a party for the "Boiler Room Girls
", a group of young women who had worked on his brother Robert's presidential campaign the year before.
Leaving the party, Kennedy was driving a 1967 Oldsmobile Delmont 88
with one of the women, 28-year-old Mary Jo Kopechne
, as his passenger, when Kennedy drove off Dike Bridge into the Poucha Pond inlet. Kennedy escaped the overturned vehicle and swam to safety, but Kopechne died in the car. Kennedy left the scene and did not call authorities until after Kopechne's body was discovered the following day.
On July 25, Kennedy pleaded guilty to leaving the scene of an accident and was given a sentence of two months in jail, suspended
That night, he gave a national broadcast in which he said, "I regard as indefensible the fact that I did not report the accident to the police immediately," but denied driving under the influence of alcohol and denied any immoral conduct between him and Kopechne.
Kennedy asked the Massachusetts electorate whether he should stay in office, and after getting a favorable response, he did.
In January 1970, an inquest into Kopechne's death took place in Edgartown, Massachusetts
At the request of Kennedy's lawyers, the Massachusetts Supreme Judicial Court
ordered the inquest be conducted in secret.
The presiding judge, James A. Boyle, concluded that some aspects of Kennedy's story of that night were not true, and that "negligent driving appears to have contributed to the death of Mary Jo Kopechne."
A grand jury
on Martha's Vineyard staged a two-day investigation in April 1970 but issued no indictment, after which Boyle made his inquest report public.
Kennedy deemed its conclusions "not justified."
Doubts about the Chappaquiddick incident generated a large number of articles and books over the next several years.