Never had any staff abusing their powers. I have had one ex-staff member that broke some of my forum's rule, however, but that's the closets thing I can relate. Most of my staff members are generally friends I've known for quite a while.
I usually have a good idea of hiring staff members, so luckily I've never had an issue with someone abusing their powers. However I have had staff that do something wrong when dealing with a situation, and I find that to be abusive. They should have warned instead of banned, etc.
However as a total AA or complete abuse of powers, no. I'd like to keep it that way as well. :lol:
When I was much younger, I had at a few times picked bad staff that would abuse their positions. Took me a bit of time to finally get to the point of knowing who to hire, and who not to hire as moderators for most of the things I work on. Granted, there are still times where someone might look like a good pick, and end up being a bad choice.
Once I agreed to take on another admin who wanted to mess up my entire forum, at least it was before it actually opened. But due to this person I decided I didn't want to open that forum anymore because many things became wasted. But usually I limit the abilities of staff unless I truly trust them a lot.
I've just recently had to demote someone this week for this very thing. We lied and deceived me about one of my co-founders, whom I've now reinstated. It pisses me off to no end when people do this, especially if they start out as good staff but then go sour right away.