Chat Rules How to modify

Summary

How to modify our Chat Rules so we receive only internal chats

Content

How do we change chat rules in Service Cloud so that only internal users can submit a chat to our group and not allow external (public) chat requests to go into our queue.  We work as a internal support group and have a internal webpage for submitting incidents and chats.  We are getting chats from external (public) customers that should not be being routed to our group and our chat, those chats should be going to a separate group that works specifically with the public. 

I have looked at the Chat - Queue routing rules and cannot determine where the change needs to be made (new to oracle).  Is the rule made on our "Incident Rule" page or is it made on another page or the page for the public group?