In 1981, shortly after Howard Liebengood was elected the 27th Sergeant at Arms of the United States Senate, he realized he had no idea how to address incoming president-elect Ronald Reagan on a visit. “The thought struck me that I didn't know what to call the President-elect,'' Liebengood told The New York Times in November of that year. ''Do you call him 'President-elect,' 'Governor,' or what?” (He went with “Sir.”)

It would not be the first—or last—time someone wondered what, exactly, a Sergeant at Arms (SAA) should be doing. Both the House and the Senate have their own Sergeant at Arms, and their visibility is highest during the State of the Union address. For Donald Trump’s State of the Union on January 30, the 40th Senate SAA, Frank Larkin, will escort the senators to the House Chamber, while the 36th House of Representatives SAA, Paul Irving, will introduce the president (“Mister [or Madam] Speaker, the President of the United States!”). But the job's responsibilities extend far beyond being an emcee.

The Sergeants at Arms are also their respective houses’ chief law enforcement officers. Obliging law enforcement duties means supervising their respective wings of the Capitol and making sure security is tight. The SAA has the authority to find and retrieve errant senators and representatives, to arrest or detain anyone causing disruptions (even for crimes such as bribing representatives), and to control who accesses chambers.

In a sense, they act as the government’s bouncers.

Senat Sergeant at Arms Frank Larkin (L) escorts China's president Xi Jinping during a visit to Capitol Hill.Astrid Riecken, Getty Images

This is not a ceremonial task. In 1988, Senate SAA Henry Giugni led a posse of Capitol police to find, arrest, and corral Republicans missing for a Senate vote. One of them, Republican Senator Bob Packwood of Oregon, had to be carried to the Senate floor to break the filibustering over a vote on senatorial campaign finance reform.

While manhandling wayward politicians sounds fun, it’s more likely the SAAs will be spending their time on administrative tasks. As protocol officer, visits to Congress by the president or other dignitaries have to be coordinated and escorts provided; as executive officer, they provide assistance to their houses of Congress, with the Senate SAA assisting Senate offices with computers, furniture, mail processing, and other logistical support. The two SAAs also alternate serving as chairman of the Capitol Police board.

Perhaps a better question than asking what they do is pondering how they have time to do it all.

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