He stated that his intent was to immediately take Kopechne to a ferry landing and return to a hotel in Edgartown, but that he made a wrong turn onto a dirt road leading to a one-lane bridge.

At a court hearing on July 25, Kennedy pleaded guilty to a charge of leaving the scene of an accident and received a two-month suspended jail sentence.

[11] Kennedy ultimately decided to enter the 1980 Democratic presidential primaries but earned only 37.6% of the vote, losing the nomination to incumbent U.S. president Jimmy Carter.

Kennedy and Gargan hosted a cookout party at the cottage at 8:30 p.m that evening,[15] as a reunion for the "Boiler Room Girls,” women who had served on Robert's 1968 presidential campaign.

As he called out to offer help, the car moved forward and veered, quickly, eastward onto Dike Road, speeding away and leaving a cloud of dust.

[31] Kennedy returned to the cottage, where the party was still in progress, but rather than alerting all of the guests to the crash, he quietly summoned Gargan and Markham, and collapsed in the back seat of a rented Plymouth Valiant parked in the driveway.

John Farrar, captain of the Edgartown Fire Rescue unit, arrived at 8:45 a.m., equipped with scuba gear, and discovered Kopechne's body in the back seat; he extricated it from the vehicle within ten minutes.

Arena then typed out the statement:[44][Notes 4] On July 18, 1969, at approximately 11:15 p.m. in Chappaquiddick, Martha's Vineyard, Massachusetts, I was driving my car on Main Street on my way to get the ferry back to Edgartown.

He signed Kopechne's death certificate to that effect, released the body for embalming, and directed that a blood sample be collected and sent to the Massachusetts State Police for analysis of alcohol content.

[46] The result was 0.09%, which Mills mistakenly thought represented only a "moderate" level, but, in fact, indicated in a person of Kopechne's weight, up to five drinks of liquor within an hour prior to death.

[48][49][50] Nevin strongly disagreed with Mills's decision to forgo an autopsy,[51] believing that ruling out foul play would work to Kennedy's advantage by laying prurient public speculation to rest.

[52] After U.S. President Richard Nixon's security operative Jack Caulfield learned of the incident, he dispatched Anthony Ulasewicz to Dike Bridge in disguise as a newspaper reporter to collect information, since he believed Kennedy would be his rival in the 1972 presidential election.

[55] Bob Molla, an inspector for the Massachusetts Registry of Motor Vehicles who investigated the crash at the time, said that parts of the roof and the trunk appeared to be dry.

Stephen Smith, Robert McNamara, Ted Sorensen, Richard N. Goodwin, Lem Billings, Milton Gwirtzman, David W. Burke, John Culver, Tunney,[41] Gargan,[60] Markham and others arrived to advise him.

[62] "Considering the unblemished record of the defendant, and insofar as the Commonwealth represents this is not a case where he was really trying to conceal his identity...", Boyle sentenced him to the statutory minimum two months in prison, which he suspended, saying that he "has already been, and will continue to be punished far beyond anything this court can impose.

"The speech concluded with a passage quoted from John F. Kennedy's book Profiles in Courage (ghostwritten by Sorensen): "A man does what he must — in spite of personal consequences".

On July 31, the same day Kennedy returned to his Senate seat,[73] Dinis wrote to the Chief Justice of the Massachusetts Superior Court, Joseph Tauro, asking for a judicial inquest into Kopechne's death.

Dinis petitioned for an exhumation and autopsy of Kopechne's body,[75] and on September 18, 1969, he publicly disclosed that blood had been found on her long-sleeved blouse and in her mouth and nose, "which may or may not be consistent with death by drowning",[78] when her clothes were given to authorities by the funeral director.

[75] Forensic pathologist Werner Spitz testified on behalf of the parents that the autopsy was unnecessary and the available evidence was sufficient to conclude that Kopechne died from drowning.

At the request of Kennedy's lawyers, the Massachusetts Supreme Judicial Court ordered it to be performed secretly[84][85] with Judge Boyle presiding, and the 763-page transcript was released four months later.

"[32] Kennedy had told Gargan and Markham not to tell the other women anything about the incident "because I felt strongly that if these girls were notified that an accident had taken place and Mary Jo had, in fact, drowned, that it would only be a matter of seconds before all of those girls, who were long and dear friends of Mary Jo's, would go to the scene of the accident and enter the water with, I felt, a good chance that some serious mishap might have occurred to any one of them.

According to Kennedy's testimony, the two men asked why he had not reported the accident, and he responded by telling them "about my own thoughts and feelings as I swam across that channel... that somehow when they arrived in the morning that they were going to say that Mary Jo was still alive.

Judge Wilfred Paquet instructed the members of the grand jury that they could consider only matters brought to their attention by the superior court, the district attorney or their personal knowledge.

[95] He cited the orders of the Massachusetts Supreme Judicial Court and told the grand jury that it could not see the evidence or Boyle's report from the inquest, which were still impounded.

[95] Dinis had attended the inquest and seen Boyle's report, and he told the grand jury that there was not enough evidence to indict Kennedy on potential charges of manslaughter, perjury, or driving to endanger.

On May 27, the registrar informed Kennedy in a letter that "I am unable to find that the fatal accident in which a motor vehicle operated by you was involved, was without serious fault on your part" and so his driver's license was suspended for a further six months.

The episode argued that the explanation would account for Kennedy's lack of concern the next morning, as he was unaware of the accident, and for the forensic evidence of the injuries to Kopechne being inconsistent with her sitting in the passenger seat.

[102] The book laments how the incident robbed Chappaquiddick of its traditional peace and privacy, attracting large tourist groups wanting to view the sites connected with the tragedy.

For example, Time magazine reported immediately after the incident that "one sick joke already visualizes a Democrat asking about Nixon during the 1968 presidential campaign: 'Would you let this man sell you a used car?'

In the episode titled “Nobody Is Ever Missing”, main character Kendall Roy leaves a party, crashes his car in a pond, and his passenger drowns to death.