The speed of the escalation is what stuns me. There is a fairly routine encounter, she calls, they respond, look around, talk to her on the porch, very calm and normal and he says something about "is there anything else we can do for you." implying they are about to leave, she responds a bit odd and he says something about, "are you doing ok, you know mentally" or something to that effect. He seems to detect that she might not be totally ok. They go in, he is getting some identification, again all calm and pleasant, she goes to move the water and he just completely changes, pulls the gun and warns her he will shoot her in the face. I don't get it. If he really felt threatened, just back off and out the front door.