Eventually, Kennedy and Rosemary "Crickett" Keough got into the Olds and set out for a visit to the beach across the famous bridge. Kennedy was at the wheel and Rosemary in the passenger seat. In the dark, they did not realize that Mary Jo was sound asleep on the back seat.
Heading toward the beach, Kennedy noticed a local patrol car and feared a DUI check that he would fail. He pulled over and slipped out of the car and into the tangle of roadside bushes. Rosemary Keough slid over behind the wheel and, following Kennedy's hasty directions, drove off toward the bridge to the beach.
Ironically, the cop in the patrol car did not pursue and, as one of the few Democrats in the local police force, he was even a Kennedy fan. Had the cop come upon the inebriated Kennedy behind the wheel of his Olds, he would have almost certainly asked for an autograph and then gotten Kennedy and Keogh (and Kopechne) safely back to the party cottage.
As it was, in utter darkness and unfamiliar with the sharp turn and downward slope toward the narrow bridge, Rosemary was going too fast and drove off the bridge into the water. She escaped, but, unaware, left Mary Jo Kopechne behind to drown.
Meanwhile, Kennedy got tired of waiting for Rosemary to return and walked back to the cottage. Kennedy, his cousin Joe Gargan, and close friend Paul Markham collaborated and assumed that Rosemary had an accident, gotten lost, or maybe had fallen asleep. They got Teddy off the island via a small boat, back to his hotel room in Edgartown and away from the scene of potential trouble.
Early the next morning, local fishermen saw the car in the water and reported it to the authorities. Soon, Gargan and Markham learned of this and met with Kennedy. The initial plan was for Gargan to take responsibility for a simple one car accident. Then Kopechne's body was found and Kennedy was stuck with responsibility.
Although loyal, Gargan was not going to incriminate himself in a death. Nor could Rosemary Keogh be thrust into the spotlight as the person responsible. Under questioning, she would soon spill the truth about Kennedy's dodgy conduct and drunken driving. The obvious nature of the party on Chappaquiddick as a no-wives-present good time with young, attractive, and willing single women would also have been put on record.
That put Ted Kennedy on the hook, with a story that evolved into five different versions -- none of which quite make sense. The local police chief was certain of one thing: there was no way that Kennedy could have been in the car because he had no injuries. And Rosemary's purse was found in Kennedy's car -- but not Mary Jo's.
Where was her underwear?