Quick response would be to hose his ass down with the gas nozzle.
I saw a video of a lady that did that and the bad guy ran like a scalded cat.
Like J Kennedy asked, what state?
If in a state that doesn't allow CCW, then the gas nozzle solution would work in your favor as it can be explained away as a "startle response" reaction to a threat.
If in a state that allows CCW, then here endeth the lesson.