WASHINGTON (CN) - The D.C. Circuit on Tuesday affirmed the constitutionality of Special Counsel Robert Mueller's appointment and upheld a contempt order for a former assistant of longtime Trump confidant Roger Stone.
"Special Counsel Mueller was properly appointed by a head of a Department, who at the time was the Acting Attorney General," the 16-page opinion states.
The unanimous ruling marks a big win for Mueller, whose authority has been under constant challenge since he brought the first indictments in connection with his investigation of Russia's interference in the 2016 presidential election.
Andrew Miller, a former Stone aide, brought the challenge after the district court held him in contempt in August for refusing to appear before the grand jury as part of Mueller's probe.
Miller's attorney, Paul Kamenar, had argued that no law allows the attorney general to appoint a private attorney as an inferior officer, and that no law contains language that specifically authorizes a department head to appoint an inferior officer.
However, a three-judge panel of the D.C. Circuit on Tuesday shot down the argument that Mueller wields so much power that his position requires presidential nomination and Senate confirmation.
The panel agreed with the government that Mueller's appointment by Deputy Attorney General Rod Rosenstein complied with the Constitution's appointment clause, which allows a department head to appoint an inferior officer, who is then supervised and directed by a presidentially appointed and Senate-confirmed officer.
The Russia probe landed in Rosenstein's lap after former Attorney General Jeff Sessions recused himself from the matter. That made Rosenstein eligible to appoint Mueller, according to the ruling.
"Because the Special Counsel is an inferior officer, and the Deputy Attorney General became the head of the Department by virtue of becoming the Acting Attorney General as a result of a vacancy created by the disability of the Attorney General through recusal on the matter, we hold that Miller’s challenge to the appointment of the Special Counsel fails," U.S. Circuit Judge Judith Rogers wrote.
Rogers was joined on the panel by U.S. Circuit Judges Sri Srinivasan and Karen Henderson.
The Office of Special Counsel declined to comment on the opinion. Miller’s attorney, Kamenar, did not return an email seeking comment on the matter, but has previously said his client intends to take the issue to the U.S. Supreme Court.
Miller could also ask the en banc D.C. Circuit to review the matter.
Tuesday’s ruling, however, means that for the time being, Miller will need to testify before the grand jury or face jail time for contempt.
The decision marks yet another rejection of challenges to Mueller's authority.
Both former Trump campaign manager Paul Manafort and indicted Russian firm Concord Management and Consulting had challenged Mueller's authority, with four district court judges - including one appointed by President Donald Trump - declining to dismiss Mueller's indictments on that basis.
Miller meanwhile had asked the district court to quash a subpoena for grand jury testimony. According to court documents, Miller sought immunity and a limit to the questions posed to him about Stone, whom he previously worked for.
Stone is facing a seven-count indictment for lying to Congress, obstruction and witness tampering over his effort to obtain information about the Democratic Party emails WikiLeaks published, which U.S. intelligence agencies say were stolen by Russian hackers and damaged Hillary Clinton, Trump’s opponent in the 2016 election.
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