Haven't been following very close. Was this a double action pistol that he had? Is he claiming that this pistol cocked it's own hammer back and fired all by itself?
It was a single action, dont know if its a Colt or what generation it is.
It also could be an Italian import, either way it could have sh!tty sear engagement with hammer pushoff and the hammer dropped from being pushed forward. The firearm examiner will say for sure.
If its pre rebound things can happen, when carried with all chambers loaded.
If it has a rebound hammer, the trigger was held back in order for it to fire.
Storys seem to be constantly changing since the discharge...