U.S. Markets open in 6 hrs 58 mins

Trump Justice chief appointment is legal: DOJ

Jeff Sessions, who served as Trump's first attorney general, met Russia's ambassador to the United States three times during the 2016 campaign (AFP Photo/Saul LOEB)

Washington (AFP) - The US Justice Department insisted Wednesday that President Donald Trump's appointment of Matthew Whitaker as acting attorney general was legal, despite Whitaker not having been confirmed by the Senate.

Faced with questions from constitutional scholars and a court challenge by the state of Maryland, the department issued a 20-page opinion which argued that conflicting laws gave the president room to appoint an unconfirmed official to the top Justice position.

They also argued that previous presidents made similar interim appointments of cabinet-level officials who had not gone through the Senate confirmation process.

"Mr. Whitaker's designation is no more constitutionally problematic than countless similar presidential orders dating back over 200 years," said the opinion by the department's Office of Legal Counsel.

"Although an attorney general is a principal officer requiring Senate confirmation, someone who temporarily performs his duties is not," it said.

Trump named Whitaker to the job on November 7 after firing attorney general Jeff Sessions after 18 months of acrimony related to the ongoing Russia collusion investigation that threatens Trump.

Whitaker had been Sessions' chief of staff and liaison to Trump for just over one year.

Before that he had a limited career as a federal prosecutor in Iowa and then as a businessman and property developer. After failing in two bids for elected office, he became a television commentator.

The legal basis for his holding the acting attorney general job is crucial: if it is found to be unconstitutional, any indictments and court decisions issued while he is in office could theoretically be challenged, according to legal experts.

On Tuesday the Maryland state attorney general, in a case pitting the state against the Justice Department, asked a federal court for an injunction, arguing that Whitaker could not legally hold his position.

Whitaker has been under fire on several fronts since Trump named him.

Taking the job gives him direct control over the Russia collusion probe led by Special Counsel Robert Mueller, which Whitaker had criticized last year before joining the Justice Department.

Top Democrats have demanded he recuse himself, as Sessions had, from the politically explosive investigation.

"There are serious ethical considerations that require Mr Whitaker's immediate recusal from any involvement with the Special Counsel investigation," senior Democrats said in a letter to the Justice Department's top ethics official Monday.