Deleted : After consideration it's not worth asking any questions. It's your website, your forums, and you hire or allow whomever you please to moderate your forums. The only infraction that matters is a ban, warnings are just words sent in a pm. So irregardless if a warning was justified or sent in error, or for other reasons its still just a pm.
Comments
When your post gets moderated, I think ideally you should first look closely at the post and think about what you did wrong, possibly about whether you should change some of your posting habits to avoid it in the future.
However, it's much more in line with human nature to look for any possible excuse that would explain why you didn't do wrong. I think that increasing transparency would only lead to people who get moderated focusing on moderators to look for that excuse, instead of looking at the reasons why their post was moderated, and do much more bad than it would do good.
If a moderator makes a mistake, complaining to [email protected] works well enough.
To give feedback on moderation, contact [email protected]