It was a majority decision among the moderators, following a series of ruthless behavior despite plenty of warnings. I also told him that on IRC after he contacted me about it the same evening.
A couple of days passed between the last report of bad behavior, the decision to ban him and the actual ban, this is maybe why Rick was puzzled for what he got banned. Also the fact that his IP got banned and he couldn't access the PM sent by the admin is unfortunate. But as I said, me and other mods talked to him on IRC. Also it is a temporary ban.
Hope that answers most of your questions.