Slashdot’s meta-moderation system worked well for a long time. One set of people could make moderation decisions directly on content, and then another unrelated set of people would review the moderation decisions and support or revert them.
It was all tied to karma and permissions in ways I can’t quite remember. But essentially there was no way for a motivated bad-faith group to both moderate and meta-moderate themselves, and the incentives marginalized bad faith actors over time.
You had limited resources to use (5 moderation points at a time for example), at least in theory. Having moderation be moderated was a great idea though I think should come back in some form.
It was all tied to karma and permissions in ways I can’t quite remember. But essentially there was no way for a motivated bad-faith group to both moderate and meta-moderate themselves, and the incentives marginalized bad faith actors over time.