In Surprise Move, Trump Taps Missouri Attorney General to Help Run F.B.I.

The Trump administration said on Monday that it had tapped the Missouri attorney general, Andrew Bailey, to be a deputy director of the F.B.I., in what many rank-and-file agents described as a surprising arrangement.

Mr. Bailey would join the current deputy director, Dan Bongino, who as a popular right-wing podcast host repeatedly railed against the bureau, in overseeing the day-to-day operations of the agency. Since taking the post — a sprawling task that includes overseeing dozens of field offices around the country, as well as personnel assigned around the world — Mr. Bongino has vocally complained about the toll the job has taken on him.

“Thrilled to welcome Andrew Bailey as our new FBI co-deputy director,” Todd Blanche, the deputy attorney general, wrote on social media. “As Missouri’s attorney general, he took on the swamp, fought weaponized government, and defended the Constitution. Now he is bringing that fight to DOJ.”

The move was reported earlier by Fox News, prompting a one-word response from Mr. Bongino on social media. “Welcome,” he wrote, followed by a trio of American flag emojis.

Mr. Trump once briefly considered nominating Mr. Bailey to be the attorney general, and during the transition discussed selecting him to be the F.B.I. director. But the president, who likes aggressive personalities, found him too laid back and somewhat lackluster, according to people briefed on the meetings at the time.

It remains to be seen what Mr. Bailey’s hiring means for Mr. Bongino, whose future has appeared tenuous after a furious fight with the attorney general, Pam Bondi, spilled into public view in July. He and Ms. Bondi had an angry confrontation in the White House in front of top aides over unreleased files in the case of the disgraced financier Jeffrey Epstein, and over whether Mr. Bongino was leaking information to the news media.

For a few days after the dispute, it was unclear if Mr. Bongino would return to work. He ultimately did, though he has kept a considerably lower profile since. People close to Mr. Trump were unhappy with Mr. Bongino’s display of anger, but believed that having him leave his job could undermine the president.

The appointment of Mr. Bailey bewildered many current and former F.B.I. agents, who said they had never heard of a co-deputy director.

An F.B.I. spokeswoman declined to comment or confirm that Mr. Bailey had been hired by the administration. Mr. Trump has a tendency to appoint one person to multiple high-level positions, and it was not immediately clear whether Mr. Bailey would have one job, or two jobs 900 miles apart.

Mr. Bailey, a Republican, has been an active ally of Mr. Trump’s, and veterans of his office have taken significant roles in the administration, including D. John Sauer, who now serves as the solicitor general of the United States, overseeing the Trump administration’s arguments before the Supreme Court.

Despite his bombastic attacks on Democrats, Mr. Bailey is a more conventional choice for the role than Mr. Bongino was, given his time in government.