It is just that right now -- behind the scenes. I would have to guess that there is some concern over controversies arising if players (even long time community members) were given any power to remove scores.
I was imagining some sort of system of checks & balances so that a single moderator having a bad day couldn't just wipe out someone's scores due to a personal vendetta or whatever. Though hopefully we'd choose people known to be saner than that (the same way forum moderators are chosen and trusted not to just delete accounts willy-nilly whenever they disagree with people).
Failing that, maybe some sort of sub-section of the message boards just for moderators to discuss before taking action. "Hey, here's a score that looks like a cheat. Anyone object to my deleting it?" Or "Hey, here's a score that should be relocated because there are two known versions of this song. Anyone know the artist well enough to verify this?" Something like that. There'd need to be enough mods for a system like that to really get some traction, though.
It'd also probably be a good idea for the system to remember deleted scores, just in case a mod goes rogue, and someone else needs to ban that person and undo their damage. But again, I'm optimistic enough to hope we could avoid that scenario by picking the right people to begin with.