[2] Traditionally the post of Serjeant-at-Arms was filled by a retired military officer, but in 2008 a civil servant, Jill Pay, was selected as the first woman to hold the appointment.

In rare cases, the Serjeant at Arms may be called upon to enforce the warrants of the Speaker in summoning a witness to testify before a select committee of the house.

While serving the warrant and encouraging a witness to attend parliament "the Serjeant or his appointee may call on the full assistance of the civil authorities, including the police.

"[4] In January 1992, the Serjeant at Arms was employed to summon Ian and Kevin Maxwell, the sons of the disgraced business tycoon Robert Maxwell, to attend an inquiry held by the Social Security Select Committee into the operation of the Mirror Group Pension fund.

[4] In November 2018, the Serjeant at Arms was called upon to escort an American businessman, who was staying in London, to the Houses of Parliament because he had documents pertaining to the Facebook–Cambridge Analytica data scandal.