Id like to help What is the method to detirmine that archival footage is authentic Looks real to me and if you watch Kellerman and Greer in the Zapruder film which the US Government accepted as authentic you can clearly see both of these individuals abandoning JFK Kellerman was specifically assigned as his body guard and was required to shield JFK with his body Johnsons SS agend did when the shooting started Instead Kellerman saw JFK was hit and then simply turned back around and sat there Greer turned back TWICE as everyone in the limo was visibly in distress His second turn sure looks unusual for someone who is trained to keep both hands on the wheel To me it looks like the Adams  Newcomb  Cooper  Robertson observations are correct and the stabilized Zapruder showing Greer turning back to fire a pistol low near his lap and NOT near Kellermans forehead is the evidence hiding in plain sight Could the shooters have been blowing it and was Greer forced to finish the job