Where does he challenge him to a duel?
It is a little difficult to tell from the language of the Tennessee constitution if issuing a challenge was itself illegal. On the other hand, baiting the mayor to rise to challenge Forrest would immediately cost him (the Mayor's) his office. The Mayor didn't rise to the bait, keeping absolutely quiet.
Forrest knew (IMHO) what he was doing.
On the other hand, Barry, why did you post this article? Can you tell me?