Online communities can allow anyone to "report" problem posts or PMs. Only the moderators see these reports, not the general membership or public. For example, Simple Machines Forum has a report link on every post.

I've been part of the moderation team in scienceforums.net for the past 6-7 years, and I can account for this from the "other side" (of a moderation team member) --- it really depends on how well the moderation team handles these reports, but from my experience, the system has great advantages-

1. It allows users to complain about anything from bias to bad attitude to stalking *privately* and without repercussion (no one other than the moderators knows that something was reported) and when we take action, we take care not to imply that anyone reported the post.

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