Special Counsel Robert Mueller III. Credit: Diego M. Radzinschi/ ALM

In oral argument before a D.C. Circuit panel Thursday afternoon, a U.S. lawyer from the special counsel's office issued a defense of Robert Mueller III's probe, fighting assertions that it's an uncontrolled investigation.

“It is not the case that the special counsel is wandering in a free floating environment and can decide” when to report to the acting attorney general, appellate lawyer Michael Dreeben said.

His defense came as a three-judge panel on the U.S. Court of Appeals for the D.C. Circuit heard arguments in a case challenging Mueller's appointment, brought by Andrew Miller, a former aide to Trump confidant Roger Stone. Attorney Paul Kamenar, who is representing Miller, has argued in part that Mueller's May 2017 appointment violated the appointments clause of the U.S. Constitution, contending that the special counsel is a principal, not an inferior, officer under the clause, which would have required a presidential appointment and Senate confirmation.

“Because of his extraordinary powers as a prosecutor, coupled with the lack of supervision and control over this conduct, the Special Counsel, like U.S. Attorneys, was required to be appointed by the President and confirmed by the Senate,” Kamenar wrote in a brief for the appeal.

On Thursday, Kamenar cast Mueller as a prosecutor with “extraordinary” power and little supervision at the Department of Justice, describing him as “like a U.S. attorney at large.”

The D.C. Circuit panel that heard Thursday's case included Judges Karen LeCraft Henderson, Judith Rogers and Sri Srinivasan. Henderson is a George H.W. Bush appointee. Rogers was appointed to the court by Bill Clinton, and Srinivasan by Barack Obama.

Srinivasan did not appear ready to take up Kamenar's position, pressing him to differentiate Thursday's case from Morrison v. Olson and a D.C. Circuit case, where courts have found that officials “with many of the same attributes” were still considered inferior officers.

Rogers asked Kamenar how he arrived at the conclusion that Mueller operated without supervision, noting that the way she read the record, “we just don't know what's going on.”

The arguments were held a day after the abrupt resignation of Attorney General Jeff Sessions, submitted at the White House's request. President Donald Trump named Matthew Whitaker, Sessions' chief of staff, to fill in as acting attorney general.

At the beginning of Thursday's session, Henderson instructed attorneys to argue as if the session were taking place before the previous day's “events.” She indicated the court would likely ask attorneys for supplemental briefing.

Thursday's case arose out of a grand jury subpoena fight involving Miller, who had sought to quash a subpoena that the special counsel's office had served against him earlier this year. Miller has so far refused to comply—he was held in contempt of court this summer—instead focusing on challenging the legitimacy of Mueller's appointment. The special counsel's office has sought to interview Stone's associates as it examines possible links between the ex-Trump adviser and the group WikiLeaks during the 2016 campaign.

There have been multiple efforts to challenge Mueller's appointment on legal and constitutional grounds. None has succeeded.

Most recently, U.S. District Judge Dabney Friedrich, appointed to the Washington, D.C., federal trial court by Trump, rejected a challenge to Mueller's appointment brought by Concord Management and Consulting, a Russian troll farm that was indicted earlier this year.

Reed Smith attorney James Martin represented the Russian company, an amicus curiae in the Miller case, during oral argument Thursday. He argued there was no statutory authority that allowed Deputy Attorney General Rod Rosenstein to appoint Mueller, because Mueller was a private lawyer at the time of his appointment.

Even so, Kamenar has already indicated he and Miller expect to lose their case before the appeals court. He told a radio show that the D.C. Circuit was full of liberals, and that they're ultimately eyeing an appeal to the U.S. Supreme Court, where they believe they'll find more a favorable reception.

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