The task of summoning the Commons to the Lords at the
State Opening falls to the Gentleman Usher of the Black
Rod. The position of Black Rod is believed to go back
almost as far the establishment of the Order of the
Garter, of which he is an officer, in 1348. The first
recorded reference to Black Rod is dated 1361. Today,
he has many duties in the House of Lords, including 'the
care and custody, and pre-eminence of keeping' of the doors
of the High Court of Parliament.
He has responsibility for admitting and excluding people from
the house, disciplining unruly members, and (at least in theory) maintaining order in the chamber. He also takes responsibility for the Royal Apartments in the Palace, including the Queen's Robing Room and the Royal Gallery.