The Senate Commandos are one of the few nonclone units in the Republic to perform special missions for the Republic, and a fierce rivalry exists between the Senate Commandos and elite clone units such as the Clone Commandos. The Senate Commandos wear a heavier version of the blue Senate Guard armor, though they do not wear cloaks. The Senate Commandos also serve as the bodyguards for Supreme Chancellor Palpatine, prior to the creation of the red-armored Imperial Royal Guards. 'Better warm up the shuttles long range transmitter.' Clone Trooper Niner to Bel before they are killed in the explosion of their ship that was caused by a Magnaguard. The Senate Commandos are often responsible for capturing and detaining suspects wanted by the Senate for questioning, and they frequently act as elite bodyguards for Senators traveling to war zones throughout the galaxy. Senate Commando Traitor Captain Argyus before being stabbed by Asajj Ventress, who replies, 'Ill tell him myself'. More aggressive than the defensively minded Senate Guard, the Senate Commandos act as an elite police unit on Coruscant and sometimes travel to distant worlds on special missions. Part of an elite branch of The Senate Guard, the Senate Commandos are a special reserve unit that performs missions for both the Senate and the Judicial Department of the Republic.
Reference Book: Star Wars Saga Edition Clone Wars Campaign Guide