Chat moderators have the ability to kick and ban other users from the chat. To identify a chat moderator, a star will be next to the name in the rail. The chat moderator right can only be given by admins, bureaucrats, or the Wikia staff.
If a user is violating any of the wiki's policies, a chatmod can react and ban the abusing user. To ban a user, you can do it directly from the chat, or by going to the user's contribs page and clicking on ban.
If a user is banned from chat, an administrator or chatmod can do it directly from the chat, or by going to the user's contribs page and clicking on unban. They will be instantly unbanned and allowed to participate in the chat.