Accountable to the community represented by the forum itself. Participants in a forum need to have some kind of skin in the game, even if it's based on their pseudonymous identity, which brings us to ...

> Pseudonomity > This has varying degrees of anonymity

By this I mean a consistent identity that has a history, credibility deriving from a track record of adhering to the community standards. It doesn't have to reference your legal identity, but things like the HN "throwaway" drive-by accounts are a problem, IMO, except in rare cases where the individual would take a great personal risk by speaking out even as their pseudonymous identity. But in that case, the bar of evidence for assertions should be very high.