The fifty years since the assassination of John F. Kennedy have done little to quell the public's interest or skepticism about who killed the president.
In 1978, however, another government committee, the House of Representatives Select Committee on Assassinations, found that in addition to Oswald, there likely was a second gunman who fired at the president's motorcade.
The commission concluded that the gunmen were part of a "conspiracy," without determining exactly who was behind it, opening the door to five decades and a cottage industry of theories.
According to a 2003 ABC News Poll, 70 percent of Americans believe Kennedy's death was "the result of a plot, not the act of a lone killer."
Fifty-one percent believe Oswald did not act alone, and 7 percent believe Oswald was not involved at all in the assassination.
In the years since Kennedy's death more than 2,000 books have been written about the assassination, many of which espouse one or more conspiracy theories. (ABC News)