While I would put nothing past CBS, those appear to be two different stills from video footage. In the second "photo" he's simply holding the gun in a different position (probably only a second or two later), and it is partially obscured.
That is the part of the picture CBS edited.
They removed the space between the rear of his leg and the hand holding the gun.This brought the gun closer to his body with the effect that the gun was partially obscured.
