There are numerous conspiracy theories regarding the assassination of John F. Kennedy on November 22, 1963 that arose soon after his death and continue to be promoted today. Most put forth a criminal conspiracy involving parties as varied as the CIA, the KGB, the American Mafia, FBI director J. Edgar Hoover, former Vice President Richard Nixon, sitting Vice President Lyndon B. Johnson, Cuban dictator Fidel Castro, anti-Castro Cuban exile groups, far right extremists, the Federal Reserve, the military-industrial complex, representatives of Big Business, or some combination of those entities and individuals.

More than one gunman

The Warren Commission findings and the single bullet theory are implausible according to some researchers.[citation needed] Oswald's rifle, through testing by the FBI, could only be fired three times within five to eight seconds of the assassination. The Warren Commission, through eyewitnesses, determined that only three bullets were fired as well: one of the three bullets missed the vehicle entirely; one hit Kennedy and passed through Governor John Connally, and the third bullet was fatal to the President. The weight of the bullet fragments taken from Connally and those remaining in his body supposedly totaled more than could have been missing from the bullet found on Connally's stretcher, known as the "pristine bullet". However, witness testimony seems to indicate that only tiny fragments, of less total mass than was missing from the bullet, were left in Connally. In addition, the trajectory of the bullet, which hit Kennedy above the right shoulder blade and passed through his neck (according to the autopsy), supposedly would have had to change course to pass through Connally's rib cage and wrist.

Witnesses

Thirty-five witnesses who were present at the shooting thought that shots were fired from in front of the President — from the area of the Grassy Knoll or Triple Underpass — while 56 eyewitnesses thought the shots came from the Depository, or at least in that direction, behind the President, and 5 witnesses thought that the shots came from two directions.

Nellie Connally was sitting in the presidential car next to her husband, Governor John Connally. In her book From Love Field: Our Final Hours, Connally was adamant that her husband was hit by a bullet that was separate from the two that hit Kennedy.

Roy Kellerman, a U.S. Secret Service Agent, testified that, "Now, in the seconds that I talked just now, a flurry of shells come into the car." Kellerman said that he saw a 5-inch diameter hole in the back right-hand side of the President’s head.

Lee Bowers was operating a railroad interlocking tower, overlooking the parking lot just north of the grassy knoll and west of the Texas School Book Depository. He reported that he saw two men behind the picket fence at the top of the grassy knoll before the shooting. However, the men had moved in front of the fence by the time the motorcade went by and the shooting occurred.

Clint Hill, the Secret Service Agent who was sheltering the President with his body on the way to the hospital, described "The right rear portion of his head was missing. It was lying in the rear seat of the car."[9] Later, to a National Geographic documentary film crew, he described the large defect in the skull as "gaping hole above his right ear, about the size of my palm."

Robert McClelland, a physician in the emergency room who observed the head wound, testified that the back right part of the head was blown out with posterior cerebral tissue and some of the cerebellar tissue was missing. The size of the back head wound, according to his description, indicated it was an exit wound, and that a second shooter from the front delivered the fatal head shot.

Ike Altgens, the AP photographer who snapped a famous photo of Kennedy reacting to the first bullet hit, was positioned on the south side of Elm Street across from the Grassy Knoll. According to Altgen, when the president's car was directly between him and the knoll, the fatal gunshot struck, "sending substance in my direction"[12]. In accordance with the laws of physics, Altgen's statement would indicate that the fatal shot was fired from the general vicinity around or behind the grassy knoll.

Rose Cherami (sometimes spelled "Cheramie") was depicted in Oliver Stone's 1991 movie JFK as a "witness." Rose Cherami was a 41-year-old drug addict and prostitute who was picked up on Highway 190 near Eunice, Louisiana, on November 20, 1963—two days before the Kennedy assassination—by Lt. Francis Fruge of the Louisiana State Police. Cherami told Fruge that John F. Kennedy would shortly be killed. Fruge did not believe her at first, but after some time of adamant speaking by Cherami, he came around. During her confinement, and prior to the time JFK was shot in Dallas, Cherami supposedly spoke of the impending assassination. After Jack Ruby shot Lee Harvey Oswald, Cherami reportedly claimed that she had worked for Ruby as a stripper, that she knew both Ruby and Oswald, and that the two men were "bed partners" who "had been shacking up for years." According to Lt. Fruge, Cherami declined to repeat her story to the FBI. She was killed when struck by a car on September 4, 1965, apparently while hitchhiking, near Gladewater, Texas. Among conspiracy theorists, the story has been considered quite credible since 1979, when an account by investigator Patricia Orr was published by the House Select Committee reviewing the JFK assassination

Suspects in Dealey Plaza other than Oswald

Numerous witnesses reported hearing gunfire coming from the Dal-Tex Building, which is located across the street from the Texas School Book Depository and in alignment with Elm Street in Dealey Plaza. Several conspiracy theories posit that at least one shooter was located in the Dal-Tex Building due to witness accounts and other coincidences including the apprehension of suspicious individuals like the "man in black leather" and ex-con Jim Braden inside the building, as well as the trajectory of the bullet which hit the curb on the south end of Dealey Plaza injuring bystander James Tague. Also of note is the scientific acoustic evidence presented to the House Select Committee on Assassinations in 1978 which pinpointed the Dal-Tex building as a possible source of gunfire.

Analysis

Former U.S. Marine sniper Craig Roberts and Gunnery Sergeant Carlos Hathcock, who was the senior instructor for the U.S. Marine Corps Sniper Instructor School at Marine Corps Base Quantico in Quantico, Virginia, both said it could not be done as described by the FBI investigators. “Let me tell you what we did at Quantico,” Hathcock said. “We reconstructed the whole thing: the angle, the range, the moving target, the time limit, the obstacles, everything. I don’t know how many times we tried it, but we couldn’t duplicate what the Warren Commission said Oswald did. Now if I can’t do it, how in the world could a guy who was a non-qual on the rifle range and later only qualified 'marksman' do it?”

Kennedy's death certificate located the bullet at the third thoracic vertebra — which is too low to have exited his throat. Moreover, the bullet was traveling downward, since the shooter was by a sixth floor window. The autopsy cover sheet had a diagram of a body showing this same low placement at the third thoracic vertebra. The hole in back of Kennedy's shirt and jacket are also claimed to support a wound too low to be consistent with the Single Bullet Theory.

More than one Oswald

Claims that Oswald was impersonated by a political decoy appeared very early in the assassination controversy. Professor Richard H. Popkin's 1966 work The Second Oswald set out a case for an impersonation of the alleged assassin. Much of this was based on eyewitness testimony, but Popkin did have a "star witness" in the person of FBI director J Edgar Hoover, who wrote a memo predating the assassination in which he warned that an impostor could be using Oswald's personal details.

More recently, the work of John Armstrong has purportedly identified the "two Oswalds" as part of an intelligence operation which originally had no connection to the assassination. However, expert analysis by the House Select Committee on Assassinations found that both "Oswalds" had identical handwriting. Furthermore, the House Select Committee on Assassinations had forensic anthropologists examine photos of Oswald (included in the set were photos that purportedly showed two different "Oswalds"), and all were consistent with a single individual.

Finally, it should be noted that in October 1981 Oswald's body was exhumed at the behest of British writer Michael Eddowes, with a view towards proving a thesis developed in a 1975 book, Khrushchev Killed Kennedy (re-published in 1976, in Britain as November 22: How They Killed Kennedy and in America a year later as The Oswald File). The examination positively identified Oswald's corpse through dental records, and also detected a mastoid scar from a childhood operation. Contrary to reports, the skull of Oswald had been autopsied and this was confirmed at the exhumation.