The Court of a Thousand Suns (Sten Chronicles Series #3)

Sten had fought his way up from slave laborer on a factory world to commander of the Eternal Emperor's bodyguard, the Imperial Gurkhas.
But during the first three months on Prime World, the most dangerous weapons Sten encountered were the well-phrased lies of Court politicians. It seemed no place for an honest fighting man. Then a bomb turned a spaceport bar and three strangers into scraps and well-mixed hamburger. The clues said "plot" and pointed right to the imperial staff.
Only quick — and bloody — work by Sten, Alex Kilgour, and a tough female detective would keep the Empire together and the Eternal Emperor alive.