Rod Rosenstein, the embattled U.S. deputy attorney general, is planning to argue before the U.S. Supreme Court on April 23, representing the United States in a criminal sentencing case.

A Justice Department spokeswoman confirmed on Friday that Rosenstein will argue in Chavez-Mena v. United States, a test of how much justification judges have to offer when deciding not to reduce a sentence within the range of federal guidelines. The representation was first reported by CNN.

Rosenstein has been the target of White House criticism in recent days, and in the current unpredictable climate his status is uncertain. President Trump reportedly has considered whether to fire Rosenstein, whose authority includes oversight of Special Counsel Robert Mueller's Russia investigation.

Rosenstein, according to NBC News, has said he is prepared to be fired.

Though the government is usually represented by lawyers in the U.S. solicitor general's office, it is not uncommon for other Justice Department officials to argue a case, sometimes near the end of their tenure.

Attorneys general Janet Reno, William Barr and Michael Mukasey each argued at least one case while in office. Sometimes the AGs have had to borrow morning coats—the usual garb for federal government lawyers arguing at the court—from lawyers in the solicitor general's office.

Both William Rehnquist and Antonin Scalia argued before the court they later joined while they were officials in the Justice Department.

It will be Rosenstein's first oral argument at the high court, but he has argued in lower courts before. In March 2016, while he was U.S. attorney in Maryland, Rosenstein argued before the en banc U.S. Court of Appeals for the Fourth Circuit in a privacy case involving cell-site location information. The appeals court in May that year, ruling for the government, said federal authorities do not need a warrant to obtain location records.

Not long after he was confirmed as U.S. attorney, Rosenstein in March 2006 argued the en banc appeal in the Fourth Circuit case United States v. Moye, a firearms case. The appeals court upheld the convictions.

“I appear in court occasionally,” Rosenstein noted on his Senate questionnaire.

On May 1, Rosenstein is scheduled to make a Law Day public appearance at the Newseum in Washington, discussing issues ranging from “the rule of law, the First Amendment and the mission of the Department of Justice.”

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