Those who defend the Warren Commission's lone gunman thesis point to key items of physical evidence tying Oswald to the crime. But skeptics point to evidence which exonerates Oswald. They can't both be right.
One possibility is that some of the evidence itself is planted, lied about, or tampered with.
An example of the conundrum: CE 399, "the magic bullet," has markings tying it to the rifle was found on the 6th floor of the Texas School Book Depository, attributed to Oswald. But Oswald's cheek failed a paraffin test given to see if he had fired a rifle that day, and CE 399 itself was found mysteriously on a hospital stretcher more than an hour after the shooting. Was CE 399 fired from the rifle at an earlier date and then planted on the hospital stretcher?
Serious allegations of tampering have been made regarding the following items of physical evidence, among others. The arguments in each case are largely circumstantial, and have varying degrees of support.
CE 399 – The "magic bullet" found on a stretcher in Parkland Hospital, with rifle markings tying it to the "Oswald" rifle.
Cartridges – Only two cartridges were turned over by the Dallas Police to the FBI initially, with a third coming later. This cartridge is dented in such a way that it could not now be fired.
Paper bag – The paper bag purportedly used by Oswald to carry the rifle into the TSBD building.
Bullet fragments – The fragments taken from victims, Governor Connally in particular.
Windshield – The windshield from the Presidential limousine, showing only a crack where some witnesses claim to have seen a through-and-through hole.
Tippit murder cartridges – Cartridge cases found at the scene of the murder of Officer Tippit.
"Backyard" photos – Photos of Oswald holding a rifle and pistol were disputed by Oswald himself.
Autopsy photos & X-rays – Photographs and X-rays of the JFK autopsy held by the National Archives, including brain photos from a supplemental exam.
Zapruder film – Recently some have even questioned the authenticity of the Zapruder film home movie of the assassination.
Kennedy's body – David Lifton has explained the discrepancy in medical reporting between Dallas and Bethesda as due to alteration of the President's body prior to autopsy.
The Paper Bag That Never Was, by Ian Griggs.
Frazier Speaks, by John Hunt.
The Magic Bullet: Even More Magical Than We Knew?, by Gary Aguilar and Josiah Thompson.
A Conspiracy Too Big?, by Fred Litwin.
Evidence of Alteration in the Zapruder Film, by Michael T. Griffith.
Why the Zapruder Film is Authentic, by Josiah Thompson.
Fallacies of the Warren Commission Solution, by Thomas Purvis.
HSCA report on the Oswald "Backyard" photos. HSCA Report, Volume VI, p.179.
HSCA report on authentication of Kennedy autopsy X-rays and photos. HSCA Report, Volume VI, p.225.
HSCA medical panel report on authenticity of Kennedy autopsy materials. HSCA Report, Volume VII, p.37.
ARRB staff memo entitled "Unanswered Questions Raised by the HSCA's Analysis and Conclusions Regarding the Camera Identified by the Navy and Department of Defense as the Camera Used at President Kennedy's Autopsy".