[thejeff]

I'm still not sure why a temp ban isn't the right step, even when "they fire off in your face".
Maybe they had a bad day. Maybe they were drunk at the time. A temp ban lets the situation cool off and lets them come back and behave if they want to.
Of course, maybe they're just jerks and the ban will wear off and they'll start back up. Then they've been given the chance and you hit them with the big hammer.
As for someone asking for a permanent ban, give them a temporary one. They don't have to come back.