OP did find. When I read that he hit the glass my first thought was "Castle Doctrine". Good job.
A few months ago I had a nut follow me around my Neighborhood. He had been riding my bumper since I had turned off the main road. I have no idea what I had done, if anything to provoke him, but I didn't go home. I drove through my neighborhood with him on my bumper the entire time, till I pulled out back onto the main road. He then broke off and went back the way we had come. I was ready with the phone to call 911. This was before I was carrying. I now keep my firearm next to my phone in the dash console.