Very, Very Sad! Condolences to both families.
I feel strongly about this. That is the double action production guns should be lowered to safe cock position (half cock). Why, because we are lowering these guns to a hot position, hammer resting on the firing pin. Also, while in the act of doing this you slip off the hammer and the trigger is fully depressed because it must be to lower the hammer all the way, the gun will fire with the persons hand back of the slide and the gun pointed hopefully, down range at a berm. Or if the gun is dropped for some reason, there is nothing to stop its firing should it land on the hammer.
As far as I know all hammered firearms have the half cock. Rule on Double action: 8.1.2.2. Further, in App. D Special conditions: para: 2, gives the penalty for not fully de-cocking.
This issue should be corrected in the rules ASAP.
Also, pray that the gun owner did not alter the safeties on the gun for his or her sake.