The 46-year-old Kennedy was shot while traveling in a motorcade in an open-top limousine as it passed the Texas School Book Depository Building in downtown Dallas at approximately 12:30 p.m. First lady Jacqueline Kennedy, Texas Governor John Connally (1917-1993) and his wife Nellie were riding with the president, and the governor also was shot and seriously wounded. Kennedy was pronounced dead 30 minutes later at Dallas’ Parkland Hospital.

Vice President Johnson, who was three cars behind Kennedy in the motorcade, was sworn in as the 36th U.S. president at 2:39 p.m., taking the oath of office aboard Air Force One as it sat on the runway at Dallas Love Field airport.

Less than an hour after Kennedy was shot, Oswald, a former Marine who had recently started working at the Texas School Book Depository Building, killed a policeman who questioned him on the street near his Dallas rooming house. Thirty minutes later, Oswald was arrested in a movie theater by police responding to reports of a suspect. Oswald was formally arraigned on November 23 for the murders of Kennedy and Officer J.D. Tippit.

The next day, Oswald was brought to the basement of the Dallas police headquarters on his way to a more secure county jail. A crowd of police and press with live television cameras rolling gathered to witness his departure. As Oswald came into the room, Jack Ruby (1911-1967) emerged from the crowd and fatally wounded him with a single shot from a concealed .38 revolver. Ruby, who operated strip joints and dance halls in Dallas and had minor connections to organized crime, was immediately detained. He claimed that rage at Kennedy’s murder was the motive for his action.

Since Oswald was killed so soon after murdering Kennedy, his motive for the crime remained unknown. On November 29, 1963, Johnson established the President’s Commission on the Assassination of President Kennedy in order to investigate his predecessor’s death. The commission was led by Chief Justice Warren, a former governor of California who was appointed to the Supreme Court in 1953. The commission also included two U.S. senators, two U.S. representatives, a former CIA director and a former World Bank president.

During its almost yearlong investigation, the Warren Commission, as it was commonly known, reviewed reports by the FBI, Secret Service, Department of State and the attorney general of Texas, and also pored over Oswald’s personal history, political affiliations and military record. The group listened to the testimony of hundreds of witnesses and traveled to Dallas several times to visit the site where Kennedy was shot.

In its 888-page report presented to Johnson on September 24, 1964 (and released to the public three days later), the commission concluded that the bullets that killed Kennedy and injured Connally were fired by Oswald in three shots from a rifle pointed out of a sixth-floor window in the Texas School Book Depository. Oswald’s life, including a visit he made to the Soviet Union, was described in detail, but the report made no attempt to analyze his motives. Additionally, the commission found that the Secret Service had made poor preparations for Kennedy’s visit to Dallas and had failed to sufficiently protect him, and concluded that Ruby had acted alone in killing Oswald.

The Warren Commission’s conclusion that Oswald was a “lone gunman” failed to satisfy some who witnessed the attack and others whose research found conflicting details in the commission’s report. A number of conspiracy theories arose, involving such disparate suspects as the Cuban and Soviet governments, organized crime, the FBI and CIA and even Johnson himself. Some critics of the Warren Commission’s report believed that additional ballistics experts’ conclusions and a home movie shot at the scene disputed the theory that three bullets fired from Oswald’s gun could have caused Kennedy’s fatal wounds as well as the injuries to the Texas governor.

In the late 1970s, the U.S. House of Representatives Select Committee on Assassinations (HSCA) launched a new investigation into Kennedy’s death. In its final report, issued in 1979, the HSCA agreed with the Warren Commission’s findings that two bullets fired by Oswald had killed Kennedy and wounded Connally. However, the HSCA also concluded there was a high probability that a second gunman fired at Kennedy, and that the president was probably assassinated as a result of an unspecified conspiracy. The committee’s findings, as with the those of the Warren Commission, continue to be debated.

The enormous volume of documentation from the Warren Commission was placed in the National Archives and much of it is now available to the public. However, access to Kennedy’s autopsy records is highly restricted. To view them requires membership in a presidential or congressional commission or the permission of the Kennedy family.