QUOTE(Newyorkbrad @ Wed 11th November 2009, 9:17pm)
QUOTE(Malleus @ Wed 11th November 2009, 8:55pm)
I don't keep track of these things, but have there ever been any arbitrators who weren't administrators?
A couple in the very early days. See [[User:NoSeptember/Functionaries#Arbitration Committee members (former)]] for the particulars, if you're curious.
If a non-administrator were ever elected as an arbitrator (which I don't especially favor but is not against policy), I think we'd have to confer adminship for the duration of his or her term. It would be very difficult for an arbitrator to review some cases without the ability to review deleted revisions, for example.
(If someone objected that we shouldn't make someone an admin who hadn't passed RfA, we could require the person to use the administrator buttons only for the purpose of his or her arbitration work, not for performing the usual roles of adminship.)
There's nothing to say that an administrator must pass "Requests for adminship" to become one. In fact, there is a diff floating around somewhere from Jimmy from within the past year saying exactly the opposite.
If someone can "win" the Arbitration Committee election, there is absolutely no reason for them to not automatically be granted adminship. Adminship is about trust, after all.
That said, as far as I'm aware, it would be trivial to have a steward create a custom user group for the English Wikipedia that only included certain user rights (like the user right to view deleted content) without including the rest of the admin package.