What Can Patrick McHenry, the Interim Speaker, Do?

Moments after the House voted to boot Representative Kevin McCarthy, Republican of California, as the speaker, one of his closest confidants, Representative Patrick T. McHenry of North Carolina, stepped up to the dais to take the gavel as the interim speaker.

Mr. McHenry, who is now serving in the role of speaker pro tempore — “for the time being” in Latin — is in uncharted territory. The vote on Tuesday to topple Mr. McCarthy was the first time in history that the House had fired its speaker.

It was also the first time that a law enacted after the Sept. 11, 2001, terrorist attacks came into force in the House, where each speaker must submit a secret list of people who could step into the post temporarily in the event of a cataclysmic event or other unforeseen vacancy.

Mr. McHenry’s name was first on Mr. McCarthy’s list of names. Under House rules, Mr. McHenry “shall act as speaker pro tempore until the election of a speaker or a speaker pro tempore” and is responsible for overseeing the election of a replacement.

The rules do not stipulate how quickly the House must move. Mr. McHenry intends to hold a speaker candidate forum on Tuesday, one week after Mr. McCarthy was deposed, meaning a new speaker will not be elected until that day at the earliest.

In the meantime, other action on the House floor, including any legislative business, is likely to be halted. House staff aides believe the acting speaker may wield the gavel only to administer the election of a new speaker.

But others argue that as acting speaker, Mr. McHenry can exercise powers beyond overseeing a speaker’s race, as long as a majority tolerates it.

“From an institutional House rules perspective, Speaker McHenry has the powers of the speakership, and he will continue to exercise those powers to the extent and degree that the majority party is willing to tolerate,” said Josh C. Huder, a senior fellow at the Government Affairs Institute at Georgetown University. “If he does something too brash or too bold, they will rein him in. And that’s really the only thing that’s governing his authority.”

House rules do not explicitly prohibit the interim speaker from adopting the powers of an elected speaker. But the rule that led to Mr. McHenry’s ascent was developed with only temporary absences in mind, not a vacant chair, according to Stan M. Brand, the former general counsel to the House. That leaves legal room for Mr. McHenry to exercise broader powers, such as conducting legislative business, if he chooses.

It is also not clear whether Mr. McHenry would be considered second in the presidential line of succession — behind the vice president — as the elected speaker of the House is. Experts said they did not believe that applied to an acting speaker.

Mr. McHenry, 47, was elected to Congress in 2004 and served as the chief deputy whip to Speaker John A. Boehner of Ohio. He worked behind the scenes to help negotiate the deal to avoid a default on the national debt in May, and he supported the stopgap spending bill on Saturday to keep the government open — deals that infuriated the Republican hard-liners who ultimately ousted Mr. McCarthy.

Mr. McHenry’s name has been floated as a permanent replacement for Mr. McCarthy, but he is not thought to be interested in the post. Still, even as a caretaker for the job, he has made his presence felt.

One of Mr. McHenry’s first moves as speaker was to evict former Speaker Nancy Pelosi from her special private quarters in the Capitol known as her hideaway, a move reported earlier by Politico.