(CNN)A federal grand jury has returned an indictment against former Donald Trump adviser Steve Bannon for contempt of Congress, the Justice Department announced Friday.

       Attorney General Merrick Garland has been under tremendous political pressure to indict Bannon since the House referred the Trump ally to the Justice Department for contempt on October 21.

       "Since my first day in office, I have promised Justice Department employees that together we would show the American people by word and deed that the Department adheres to the rule of law, follows the facts and the law, and pursues equal justice under the law," Garland said in a statement Friday. "Today's charges reflect the Department's steadfast commitment to these principles."

       READ: The indictment against Steve Bannon for contempt of Congress

       Bannon, 67, was charged with one count related to his refusal to appear for a deposition and another related to his refusal to produce documents. Each count carries a minimum of 30 days and a maximum of one year in jail, the Justice Department said.

       Without an indictment, critics have said, there's doubt over how much power the House January 6 select committee has to compel cooperation from former White House and Trump administration officials. Friday, former White House chief of staff Mark Meadows failed to appear for a deposition, sources familiar with the investigation told CNN, setting up a potential showdown that could lead to the panel beginning a criminal referral process against him as well.

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       And last week, former Trump Justice Department official Jeffrey Clark, who had been subpoenaed, appeared before the committee for more than an hour but declined to answer questions.

       "The grand jury was presented with overwhelming and irrefutable evidence of Steve Bannon's violation of a congressional subpoena," Rep. Jamie Raskin, a Maryland Democrat who's a select committee member, told CNN.

       "The justice system of the United States is not going to tolerate these contemptuous violations of the rule of law," he added.

       Bannon did not immediately respond to a request for comment. He is expected to self-surrender on Monday and appear in court Monday afternoon, according a source familiar with the matter. The case has been referred to District Judge Carl Nichols, who was appointed by Trump.

       The House January 6 committee subpoenaed documents and testimony from Bannon in early October.

       Bannon's lawyer, Robert Costello, told the committee the former Trump adviser would not be cooperating with the investigation because he had been directed not to by Trump. Pointing to claims from the former President that the documents and testimony being sought were potentially protected by executive privilege, Bannon's lawyer told the committee that "the executive privileges belong to President Trump" and "we must accept his direction and honor his invocation of executive privilege."

       Biden says DOJ should prosecute those who defy January 6 committee subpoenas

       President Joe Biden's White House has declined to assert executive privilege regarding witnesses and documents related to January 6, citing the extraordinary nature of the attack on the Capitol. The White House counsel's office has written to Bannon's attorney to tell him it won't support his refusals to testify.

       The White House declined to comment on Friday's indictment.

       Bannon's role on January 6

       In seeking his cooperation, the committee has pointed to reports that Bannon spoke to Trump in the lead-up to the Capitol riot, that he was present in the so-called "war room" of Trump allies at the Willard hotel in Washington as the attack was unfolding and that he made comments on his podcast the previous day predicting that "all hell" was "going to break loose" the next day.

       "In short, Mr. Bannon appears to have played a multi-faceted role in the events of January 6th, and the American people are entitled to hear his first-hand testimony regarding his actions," the House committee said in its report putting forward a contempt resolution against Bannon.

       Legal experts also have expressed skepticism about Bannon's decision not to comply with the subpoena, given that the question of whether Trump as a former President can assert privilege is unsettled and that Bannon was not working for the government in the period being examined by the committee.

       The criminal case against Bannon could take years to unfold in court, and a successful prosecution isn't a certainty. Historically, criminal contempt of Congress cases have been derailed by juries sympathetic to the defendants and by appeals rulings. Bannon's case is likely to raise novel legal questions about executive privilege and about the House's ability to enforce its investigative subpoenas when it seeks information about the executive branch.

       The House has pinned its hopes on the prosecution of Bannon as well, with the committee trying to make him an example of the possible consequences for uncooperative witnesses.

       Democratic Rep. Pete Aguilar of California told CNN that Meadows should be watching closely after skipping Friday's deposition appearance.

       "Mark Meadows should take note," Aguilar said. "We expect answers to lawful subpoenas."

       Select Committee Chairman Bennie Thompson, a Mississippi Democrat, and Vice Chairwoman Liz Cheney, a Wyoming Republican, said in a statement on Friday that Meadows' actions force the panel to consider criminal contempt against Trump's former chief of staff.

       "If his defiance persists and that process moves ahead, the record will reveal the wide range of matters the Select Committee wished to discuss with Mr. Meadows until his decision to hide behind the former President's spurious claims of privilege," the lawmakers said.

       This story has been updated with additional information.

       CNN's Tierney Sneed, Annie Grayer, Lauren Fox and Dan Berman contributed to this report.