Only once. While I could still get around without a mobility chair. The forestry service (state) had a fellow that claimed he wasn't responsible for a fire that had started where he was logging. We figured it was intentionally set, but there was really a shadow of a doubt, so they didn't nail him for it. Forest fires are no joke and it was quickly contained, but he could have caused danger like the thousands of acres of California, Oregon and Washington are so prone to have.
I've gotten requested to serve three times since I got too handicapped and too old to be of use to such a thing.