I personally don't know Michael Addison. I don't know what he is like, I don't know anything about his family life, and I don't know anything about his problems, issues, or anything else he may have going on. So I can't say anything either way about his state of mind when he was arrested. However, I do believe he shot Michael Briggs.
I have to admit that I am biased; I knew Briggsy, as did most of us who work in Manchester. He was a good cop, a nice guy, and he did his job well. He and his partners on the bikes were out all the time in the middle of the night, and whenever we got a call in the Center City area they would either be on scene when we arrived or would get there shortly after we did. They always secure our scene before we see anyone, and we appreciate that greatly.
Not that I knew Mike well; I didn't. But I got to see him often enough that I could tell he was, without a doubt, one of the good guys. And Michael Addison took him away from everyone: his family, his friends, and a city who will miss his presence.