Commissar

Commissars are tasked with maintaining the morale of Imperial troops and ratings during the Imperium's military campaigns, often in the face of staggering casualties. The commissar is empowered to use any means necessary to ensure the loyalty and moral purity of his or her charges, including overriding or even executing a regiment's commanding officer if necessary, and so is regarded with a mixture of fear, loathing and admiration by rank-and-file guardsmen -- and not a few of their officers.