Just echoing what Hellboy said, we have no ability to monitor in-game chat. If you see something, please report it. Joe has been posting vile shit in the shoutbox, which we can see. If you have any issues of players harassing others in-game please take a screenshot and report it.
As much as some of the player base would like to believe otherwise, AA2 is and always was meant to be enjoyed by everyone. Nobody should feel unsafe or harassed for simply playing a game.
Edit: And since joe is such a controversial subject, even without using him as an example the issue of using admin discretion is still present. If you're going to ban for speech, provide a set of rules so there is a clear delineation of what is allowed or restricted.
As Hellboy said (in much more professional terms than I will use here)
Just don't be a fucking asshole. That's it. Do not harass others, do not use slurs. Is this really needed to be specified? This is basic human decency and if you can't follow it you have much bigger problems than being banned in a 20 year old game.