The Ambassadorial Commission was an executive body within the Sith Empire. As of 3956 BBY, it maintained operations at the Sith Embassy on Manaan. The Ahto City Civil Authority charged Revan with murdering members of the Ambassadorial Commission after he infiltrated the Embassy during his quest for the Star Forge.
The Arbiter Bwa'lass mentions this organization by name while listing the crimes Revan had been charged with after the raid on the Sith Embassy.