The Imperial President
The Imperial President has the farest responability in the Republic. The first President is Stebb Darkbone. He use a SSD. If he should be dethroned, he could keep his ship if The Group thinks so, because the President post is not just a military post, it's a political post with no realy need for a great battle ship.
The Imperial President is a part in The Group. He has is able to veto all decisions apart from the decision about let it become a public voting in the issue of the presidents dethroning.