Usually I like moderator actions and the reasons for them to be public. The community can examine them and is either convinced that they are correct, or they can make an argument why they were not.
But there are certain actions that are based on secret or private information that can not or should not be made public. Making that information public might reveal details about abuse prevention mechanism that need to be secret to work, or it might infringe on the privacy of a third user.
Such cases can be rather problematic because the community can't see why the action is justified and there is plenty of room for speculation. And sometimes just repeating "Trust me, we have our reasons" doesn't cut it.
What are ways to deal with such situations more effectively?