(CNN) More than a decade before he was assigned the criminal contempt case brought against Steve Bannon, Judge Carl Nichols was a top Justice Department lawyer deeply involved in pushing sweeping arguments in favor of shielding an ex-presidential adviser from congressional testimony.
Nichols -- who was appointed to the bench in 2019 by former President Donald Trump -- will now oversee the Justice Department's case against Bannon, a former Trump adviser, for Bannon's alleged noncompliance with the House's January 6 investigation.
Just as notable as the president who put Nichols on the bench is the judge's experience defending Harriet Miers, who served as White House counsel to President George W. Bush, when lawmakers brought civil litigation against her for her refusal to show up for testimony subpoenaed by the House. Bannon has pleaded not guilty, and if the case goes to trial, it could be a jury that ultimately determines his guilt. But Nichols will be deciding crucial legal and procedural questions that arise before and during an eventual trial.
"That experience -- it gives him a lot of foundation for some of the arguments that Bannon is likely to raise," said Jonathan Shaub, a University of Kentucky Rosenberg College of Law professor and expert in privilege issues.
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The claims the Bush Justice Department made in court -- including in oral arguments presented by Nichols himself, then a principal deputy attorney general -- were rejected in district court and the dispute was eventually settled by the Obama administration before an appeals court could fully weigh in on the merits.
Nonetheless, the Miers case featured prominently in the subpoena battles of the Trump administration, which have set the stage for the coming court fights over Congress' probes into the Capitol riot.
Prosecutors will be grappling with legal questions unique to the Bannon case that could complicate the Justice Department's path to a Bannon conviction. But some of those distinctions may make it easier for Nichols to issue decisions against the Trump ally, legal experts say -- whatever sympathy the judge still has for the arguments he made over a decade ago.
"I do think that that if there's one judge that knows the issue well, it would be Judge Nichols," said Rick Kaplan, a lawyer who represented the House committee in in the Miers case. "A case like Miers hadn't come up in many, many years before that, so it was breaking new ground."
Miers was subpoenaed by a Democratic-controlled House in its investigation into the firings of several US attorneys under President George W. Bush. The case was an exceedingly rare occurrence of Congress trying to use civil litigation to enforce compliance with a subpoena of an executive branch official.
Miers had already left her role as White House counsel at the time she was subpoenaed, but the Bush administration argued that since the inquiry concerned her work as a close presidential adviser, she was shielded by an absolute immunity that allowed her to avoid even appearing for testimony -- arguments that were echoed by the Trump administration when the House sued Trump's former White House counsel Don McGahn in 2019 for his refusal to comply with a congressional subpoena.
Nichols presented the DOJ's arguments in the Miers case when it was heard in the district court and when it was before a DC Circuit appeals court panel.
"I think our briefs make clear that the need for immunity is based not just on the need to protect the President's interest in confidentiality, which can be protected at least in some ways by executive privilege but also the ability to protect the President's autonomy and how he exercises his constitutional duties and obligations," Nichols said at a July 2008 district court hearing in the case.
The Justice Department -- in briefs signed by Nichols and other top Bush DOJ officials -- argued not just that Miers was constitutionally immune from showing up to testify, but that the judicial branch had no authority to settle the civil lawsuit brought by Congress. (That argument won't be available to Bannon as he faces a criminal prosecution from the executive branch.)
"Judge Nichols, at the time, presented the executive branch's arguments, which are very aggressive in their in their views on the ability [presidential] advisers to refuse to turn over information," said Emily Berman, a professor at University of Houston Law Center who had submitted a friend-of-the-court brief in the Miers case on behalf of several public interest organizations.
"He'll be quite familiar with the issues and hopefully, at least, it will allow him to rule relatively expeditiously on some of these things," Berman said. "But I think it is significant that he's got a history of defending aggressive interpretations of executive privilege."
The arguments Bannon is now making to justify not participating in the current House probe are even more aggressive than the claims the Bush DOJ made in the Miers case, Berman said. And it's worth noting that just because a lawyer makes certain arguments on behalf of a client -- which, for Nichols in the Miers dispute, was the US government's executive branch -- doesn't mean that the lawyer personally agrees with those arguments, or that he will carry them with him to the bench.
In his two-plus years on the bench, Nichols has made several rulings against the interests of the President who appointed him.
Nichols shot down the Trump administration's attempts to ban TikTok and refused to dismiss a defamation lawsuit against Trump allies for their false 2020 election fraud claims. He also rebuffed Trump arguments in a case concerning potential disclosure of his tax returns to Congress.
Bannon is facing a criminal prosecution from the Biden administration, which acted on a referral from the House, whereas the Bush Justice Department declined to prosecute Miers, prompting lawmakers to bring a civil lawsuit against her instead.
The issues raised by the Miers case and the Bannon case aren't the same, said Jody Hunt, a former top DOJ lawyer who was involved in the Miers case.
"But I do think the fact that Judge Nichols had handled those other matters gives him an experience that's helpful in his assessments, because he understands a lot about these issues already," Hunt said.
In the Miers case, the DOJ argued that the court should not get involved in the dispute because criminal contempt -- as well as tools held by lawmakers, like executive branch funding decisions and nominee confirmations -- were the appropriate avenues for pressuring compliance with subpoenas. In the district court arguments, Nichols described the department's view that "Congress cannot sue the executive branch in federal court seeking information it had subpoenaed from the executive branch in aid of its legislative function."
Nichols also emphasized the 200-year tradition of Congress and the executive branch negotiating accommodations around subpoena compliance, arguing that a court intervention in the dispute would spoil that process. Department lawyers stressed in the case how the Bush administration had accommodated some of the Congress' information requests before reaching the impasse over Miers' testimony.
Bannon notably did not engage at all in negotiations with lawmakers about cooperating, beyond a letter his attorney sent the House January 6 committee informing lawmakers that he would be following former President Trump's directive not to participate in their investigation.
"I think Bannon has made it easier on DOJ -- and on Nichols in adjudicating this -- by just sort of totally not complying because, privilege: one, it's qualified. It only applies to certain information. And there's this tradition of negotiating," Shaub, who worked for the Justice Department under the Obama administration, told CNN.
While Miers, like Bannon, was not a government official when Congress was seeking her testimony, lawmakers' interest was in events that occurred during her service at the White House. Bannon -- as lawmakers are pointing out now -- was long out of the White House when the Capitol riot and the related events unfolded.
But because this is a criminal prosecution, and not a civil matter, there will be hurdles the Justice Department will have to overcome that were not present when the House was seeking to order Miers' compliance with the US Attorneys probe subpoena.
One possible question in the Bannon case is the weight that can be given to a former president's assertion privilege, as Biden has waived privilege for the purposes of the House's requests of Bannon, while Trump -- in a separate civil case concerning presidential records -- is claiming his assertion privilege can override Biden's waiver of it.
For Bannon to be found guilty, prosecutors will have to prove -- perhaps ultimately to a jury -- that Bannon had a willful intent to defy Congress' subpoena. Bannon's lawyers are likely to argue he had a good faith reasons for not showing up to testify, claiming he was following the former President's directive and the advice of his attorneys.
"Whereas in the Miers litigation, the sort of ambiguity was acceptable and the court is trying to resolve these questions of privilege and immunity," Shaub said. "Here if there's ambiguity in the law, it's going to be construed in favor of Bannon, because he's a criminal defendant."