Who Killed JFK? Inside America's Favorite Conspiracy Theory

Americans disagree about almost everything. Pineapple on pizza. Daylight saving time. Whether a hot dog is a sandwich. But ask them who killed John F. Kennedy and something strange happens: most of them agree the official answer is wrong.

In 2023, sixty years after the assassination, Gallup found that 65 percent of Americans believe others were involved, compared with 29 percent who think Lee Harvey Oswald acted alone. At its peak, in 1976 and again in 2001, the number hit 81 percent. No other conspiracy theory comes close to that kind of staying power. This is the big one. The original rabbit hole that every other rabbit hole is measured against.

Twelve-thirty in Dallas

On November 22, 1963, President Kennedy's motorcade turned into Dealey Plaza in Dallas, Texas. The roof of the limousine was down. Jacqueline Kennedy sat beside him in a pink suit. Texas Governor John Connally and his wife sat in front.

At about 12:30 p.m., shots rang out. Kennedy was hit in the upper back and then in the head. Connally was seriously wounded. The president was declared dead at Parkland Memorial Hospital about half an hour later.

Police found a rifle and three spent cartridges on the sixth floor of the Texas School Book Depository, a warehouse overlooking the route. Within hours they had arrested a 24-year-old employee of the building, Lee Harvey Oswald, a former Marine who had defected to the Soviet Union in 1959 and come back to the United States in 1962. Oswald denied everything. "I'm just a patsy," he told reporters.

Two days later, as he was being moved through the basement of Dallas police headquarters, a nightclub owner named Jack Ruby stepped out of the crowd and shot him dead, live on national television. Whatever Oswald knew, he took it with him. That single moment did more for conspiracy theories than any book ever written.

The official answer

President Lyndon B. Johnson set up a commission led by Chief Justice Earl Warren to investigate. In September 1964, the Warren Commission concluded that Oswald fired three shots from the sixth-floor window and acted alone, and that Ruby also acted alone.

The report was 888 pages long, and it satisfied almost no one for very long.

The magic bullet

At the heart of the doubt is a single bullet, known in evidence as Commission Exhibit 399. The commission concluded that one shot passed through Kennedy's neck and went on to wound Connally in the back, chest, wrist and thigh. Critics nicknamed it the "magic bullet", because the path seemed impossible and the bullet was found in near-pristine condition on a stretcher at the hospital.

Supporters of the single-bullet theory argue that the path makes sense once you account for where the two men were actually sitting, with Connally lower and further inboard than Kennedy. Skeptics argue that it was the only way to make three shots fit the timeline. Both sides have been firing reconstructions at each other for six decades.

The film, the knoll and the head snap

The most famous evidence was not filmed by any agency. It was filmed by Abraham Zapruder, a local dressmaker standing on a concrete pedestal with a home-movie camera. His 26 seconds of color footage captured the shots, including the fatal one.

In it, Kennedy's head moves sharply backward and to the left. To many viewers, that looked like a shot from the front, from the grassy knoll to the right of the motorcade, rather than from the Depository behind. Several witnesses said they heard shots from that direction. Medical and ballistics experts have offered explanations for the movement, including a neuromuscular reaction. The phrase "back and to the left" has never really recovered.

When Congress said "probably"

In 1979, the House Select Committee on Assassinations reached a conclusion that still gets quoted constantly. It agreed that Oswald fired the shots that killed Kennedy, but said he "probably" did so as part of a conspiracy. The main reason was an audio recording from a police motorcycle radio, which acoustic experts said contained evidence of a fourth shot from the grassy knoll.

In 1982, a panel from the National Academy of Sciences reviewed the recording and concluded the sounds were made about a minute after the shooting, so they could not be gunshots. The committee's "probably" stayed in the history books anyway. That is how rabbit holes work: the claim travels faster than the correction.

The suspects

Over the years, almost everyone has been accused. The CIA, angry about the Bay of Pigs. The Mafia, angry about Attorney General Robert Kennedy's crackdown on organized crime. Fidel Castro. The Soviet Union. Anti-Castro Cuban exiles. Texas oil money. The military-industrial complex. Lyndon Johnson himself. In Gallup's 2023 poll, the most common answer among those who suspect a conspiracy was some part of the US government.

Each theory has its own threads. Oswald visited the Cuban and Soviet embassies in Mexico City weeks before the assassination, and the CIA was watching. Ruby had links to organized crime. Records went missing, and witnesses told different stories. None of it has produced proof of a second shooter. All of it has produced books.

The files that never quite end

In 1991, Oliver Stone's film JFK put the conspiracy case in front of millions of people. The public anger it caused helped push Congress to pass the JFK Assassination Records Collection Act in 1992, ordering the government to release its records, with a deadline of 2017.

Most were released. Some were held back, then released in batches by successive administrations. In 2025, the government released much of what remained. Researchers have found plenty of embarrassing detail about what the CIA and FBI knew about Oswald, and about how much they kept from investigators. What they have not found is the smoking gun.

Which, for a true believer, is exactly what a cover-up would look like.

Why this one never dies

The Kennedy assassination is the perfect storm for a conspiracy theory. A young, glamorous president killed in public. A suspect silenced before trial. A government investigation that later turned out to have been kept in the dark by its own agencies. Then the 1960s and 1970s, with Vietnam and Watergate, taught a generation that official stories could be false.

There is also something harder to measure. It feels wrong that one unremarkable man with a mail-order rifle could change the course of history. A conspiracy, however frightening, at least suggests that events have a design. The lone gunman suggests something scarier: that the world can turn on a single, random act.

The verdict

Every official investigation has concluded that Oswald fired the shots that killed President Kennedy. No hard evidence of a second gunman has ever held up. But the government also withheld information for decades, and its agencies were less than honest about what they knew. That gap, between what was proven and what was hidden, is where America's favorite conspiracy theory lives. Sixty years on, it is still paying rent.

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