Insiders have a different story that the government, simple as that. The Zapruder shows three shots hitting Kennedy at once. Eyewitnesses say Oswald was at the theater when Tippet was killed. Kennedy didn't have earlobes, many of the autopsy photos show a man with earlobes. Doctors say Kennedy was shot in the front with a large exit wound to the back. Eyewitnesses say there was a hole in the windshield. A Ford engineer says the windshield was replaced immediately. Brain debris was thrown backward, not forward. Eyewitnesses say a loud shot came from the knoll. Doctors at Parkland say the back wound only went in two inches. Eyewitnesses at Tippet's murder say it was a bigger guy than Oswald that did it and his clothes didn't match what Oswald was wearing at the theater. A police car was seen honking outside of Oswald's house right before Tippet's murder. Thread patterns on the magic bullet don't match Kennedy's shirt or jacket...I could go on.
That's just too many anomalies for the government's story to be true.