I wrote:

...

One solution might be to designate a few trusted individuals as volunteer "judges" -- people to whom Jimbo in his capacity as dictator grants the authority to take action instantly, if they feel conditions warrant. The decisions of judges, of course, would be subject to review by the arbitration committee, and a judge who repeatedly abuses his authority would have it revoked.

To which Mark Pellegrini replied:

Well, if this is done, I'm not sure why we'd really need the arbitration committee. Just to rubber-stamp judge decisions?

No, not at all. Perhaps I should change my metaphor. Instead of "judges" and "arbitration committees," perhaps it would be better to use terms like "police" and "juries," along the lines that Ed Poor has suggested (see below).

What we're dealing with fundamentally is the need to have some system of governance for the Wikipedia. Everyone here (myself included) wants to have "as little government as possible," but we need SOME rules and SOME enforcement. On Wikipedia, we don't have to worry about the worst kinds of crime, like murder or even theft of property, but an aggressively obnoxious person can do more harm than we ought to tolerate. The situation is rather akin to throwing a party in your home. Jimbo has invited everyone in the neighborhood, but if some jerk shows up and starts harassing the other guests, it would be inconsiderate of the other guests if Jimbo DIDN'T tell the jerk to leave. And as owner of the house, he's entitled to do that. If the party is large enough and Jimbo can't do this entirely on his own, he's entitled to ask some other people he trusts to police the party as his surrogates.

In most effective systems of government, there is a division of labor. In the U.S. federal government, we have the legislative branch (whose job is to write laws), the executive branch (whose job is to implement and enforce them), and the judiciary (whose job is to determine interpret the laws and their enforcement). Of course, this isn't a perfect system (nothing is), but it accomplishes certain worthwhile things: (1) it creates a division of powers, which reduces arbitrariness and abuse; and (2) it encourages public ACCEPTANCE of the government's actions.

We have a similar system in the town where I live: A city council that passes local ordinances (the legislative branch); a mayor and police who enforce laws (the executive branch); and local courts where people can seek judgment if they have disputes (the judiciary). Each branch performs a necessary but separate role. The legislators establish the rules governing police and the mayor as well as everyone else. The police perform a necessary role, but they can't simply arrest someone without cause because they know they have to be able to defend their actions in court if they are sued. The courts do not simply "rubber-stamp" decisions by police and the mayor, although often the courts rule in favor of the police.

One of the reasons to have police and a mayor is SPEED OF ACTION, because they don't have to go through a deliberative process like a courtroom before they can take any action. Imagine that you see a crime in progress in your neighborhood and your only recourse is to initiate a lawsuit. By the time you even got a court date set, the criminals would have completed their crime and be long gone.

Ed Poor also responded to my suggestion, writing:

Should we invest some users with authority which elevates them from "vigilantes" and makes them more like a police force ("judges", as Sheldon put it)?

This is essentially Erik's idea, dressed up in an official uniform (hope I'm not being tactless, here :-)

Actually, though, the point is that people who are invested with authority ("dressed up in an official uniform") are NOT vigilantes. A vigilante is someone who acts as a law unto himself and who is therefore himself a law-breaker rather than an enforcer of laws.

Of course, the difference between vigilantism and police is not always this clear-cut (a theme that has been explored in several Clint Eastwood movies), but the basic idea works. We authorize police to issue fines and arrest people -- even using physical force if they deem it necessary -- precisely because we don't want EVERYONE in society using force to have their way. If we are wise, we also limit police abuses by having clear laws that limit their powers, providing them with training in proper police procedures, and having courts that are willing to curb abuses when necessary.

If all of this sounds like a lot of work, it can be. But it's also a lot of work for Wikipedians to be continually agonizing anew over how to deal with the latest troll.