1. theymos and Stefan Thomas have db access, and at least some of the former admins can decrypt forum backups (not sure if they have access to newer backups, and not sure if BadBear has access to unencrypted ones too).
edit: just found the post I was looking for:
In another thread you said that database dumps can be downloaded by other admins, but only you, Gavin, Satoshi and Sirius can decrypt them.
What does "direct database access" refer to? Any admin can query the db directly and e.g. dump it and/or read PMs?
It's not about ST being an admin now; it's just a general question which popped up in my mind when I read this announcement.
Global moderators can download the encrypted database backups. Admins and past admins (Gavin, Satoshi, Sirius, me, and now justmoon) can decrypt them -- they therefore have complete access to the database and can read PMs, etc. Justmoon and I can also query the live database.
2. Global mods and admins can ban all users, other mods can only ban (nuke) newbies.
3. Admins. If a user was banned erroneously, the ban can be rescinded. I don't think mods are offered bribes big enough to even hesitate for a moment

The highest amount someone (connected to a mining manufacturer) offered me to ban someone was $10k and I declined.