Why would self-policing not be effective? Everyone who is a member here is an adult - or supposed to be one. The staff should not have to spell out every single rule for our members to know what is not okay, when it's not okay.
"Be civil, be polite, be respectful."
This is all we really should need to police the shoutbox. Members shouldn't be afraid to step up and say "Hey, can you guys get a room?" or "Chill out - you shouldn't be calling people names" or even "You know, I think that might be more suitable for a rant than for a 100-line monologue in the shoutbox". That is mature, responsible behavior. Every member on E is capable of that.
We don't need more rules to 'police' the shoutbox. We don't need a staff member just to sit on the shoutbox to wait for a mistake to happen.
In light of new posts: Making the shoutbox "private" (members-only) isn't much of a solution, considering that the problem right now is our member base.
We expect you guys to be responsible when there isn't a staff member around. We trust that if you see something going on that shouldn't be, then you will take the initiative and give a gentle nudge so that things remain as they should be.
And hey, you know what? If you guys can't play with your toy responsibly, it's not that difficult for us to get rid of it.