“No matter who I put in, they go after him,” Mr. Trump said of his appointees. “It’s very sad.”
One criticism of Mr. Trump’s decision to appoint Mr. Whitaker is that it goes against the Justice Department’s succession plan to turn first to the deputy attorney general — Mr. Rosenstein — when the top job is vacant. The president has publicly criticized Mr. Rosenstein, as well.
Senator Richard Blumenthal, Democrat of Connecticut, said in an interview on Friday that he was considering filing a lawsuit to contest Mr. Whitaker’s appointment, most likely on grounds raised by Mr. Schumer.
“There are a number of very serious constitutional issues raised by this deeply flawed appointment,” Mr. Blumenthal said.
Mr. Trump, however, has authorities provided in a separate law that gives him options for making temporary appointments without Senate confirmation.
Speaking to reporters on Friday morning, Mr. Trump bristled at criticism that Mr. Whitaker was not the right choice to run the department, because, as Mr. Schumer said, Mr. Whitaker was not currently serving in a Senate-confirmed position.
“Mueller was not Senate confirmed. So, he’s doing a report. He wasn’t Senate confirmed,” Mr. Trump said. “Whitaker was Senate confirmed. And now he doesn’t need this, but he was Senate confirmed at the highest level when he was the U.S. attorney from Iowa.”
Mr. Whitaker was confirmed by the Senate when he served as the United States attorney for the Southern District of Iowa during the George W. Bush administration. But so was Mr. Mueller. In 2001, Mr. Mueller was confirmed by the Senate to be the F.B.I. director. And he went through previous Senate confirmations to serve as the United States attorney in the Northern District of California as well as when he served as the assistant attorney general at the Justice Department in the early 1990s.
The special counsel position is not one that requires Senate confirmation.