To be able to moderate content a User must be given Advanced Permissions like this:

• he must be allowed to edit Posts or Comments other than his own
• he must also be allowed to create Posts or Comments on at least two different Visibility Statuses from the following list of statuses:
  • Draft
  • Review
  • Member
  • Community
  • Published

See List of Permissions for details about setting these permissions.

Note: the Content Moderator User may often have inherited these permissions from his User Group.