James Carothers Garrison was the District Attorney of Orleans Parish, Louisiana, from 1962 to 1973 and later a state appellate court judge. A member of the Democratic Party, he is best known for his investigations into the assassination of John F. Kennedy and the prosecution of New Orleans businessman Clay Shaw to that effect in 1969, which ended in Shaw's acquittal. He wrote three published books, one of which became a prime source for Oliver Stone's film JFK in 1991, in which Garrison was portrayed by actor Kevin Costner, while Garrison himself also made a cameo appearance as Earl Warren.

On November 22, 1963, John F. Kennedy, the 35th president of the United States, was assassinated while riding in a presidential motorcade through Dealey Plaza in Dallas, Texas. Kennedy was in the vehicle with his wife, Jacqueline, Texas Governor John Connally, and Connally's wife, Nellie, when he was fatally shot from the nearby Texas School Book Depository by former U.S. Marine Lee Harvey Oswald. The motorcade rushed to Parkland Memorial Hospital, where Kennedy was pronounced dead about 30 minutes after the shooting; Connally was also wounded in the attack but recovered. Vice President Lyndon B. Johnson was hastily sworn in as president two hours and eight minutes later aboard Air Force One at Dallas Love Field.