WASHINGTON (Reuters) — Steve Bannon, a key associate of former President Donald Trump and an influential figure on the American right, was convicted on Friday of contempt of Congress for defying a subpoena from the committee investigating last year’s attack on the U.S. Capitol, a major victory for the Democratic-led panel.

A jury found Bannon, 68, guilty of two misdemeanor counts for refusing to provide testimony or documents to the House of Representatives select committee as it scrutinizes the Jan. 6, 2021, rampage by Trump supporters who tried to upend the results of the 2020 presidential election.

Each contempt of Congress count is punishable by 30 days to one year behind bars, as well as a fine of $100 to $100,000.

The verdict by the jury of eight men and four women, after less than three hours of deliberations, marked the first successful prosecution for contempt of Congress since 1974, when a judge found G. Gordon Liddy, a conspirator in the Watergate scandal that prompted President Richard Nixon’s resignation, guilty.

Bannon was a key adviser to Trump’s 2016 presidential campaign, then served as his chief White House strategist during 2017 before a falling out between the two that was later patched up. Bannon also has played an instrumental role in right-wing media.

His defense team in closing arguments on Friday suggested to jurors that Bannon was a political target and painted the main prosecution witness as a politically motivated Democrat with ties to one of the prosecutors. The prosecution countered that Bannon showed disdain for the authority of Congress and needed to be held accountable for his unlawful defiance.

Prosecutor Molly Gaston told jurors the attack represented a “dark day” for America, adding, “There is nothing political about finding out why Jan. 6 happened and making sure it never happens again.”

Evan Corcoran, one of Bannon’s attorneys, told jurors, “The question is, ‘Why? Why was Steve Bannon singled out?'”

The trial featured two days of testimony. Prosecutors questioned only two witnesses. The defense called none.

The conviction may strengthen the committee’s position as it seeks to secure testimony and documents from others in Trump’s orbit. Trump last year asked his associates not to cooperate with the committee, accusing it of trying to hurt him politically, and several of them rebuffed the committee.

Another former Trump adviser, Peter Navarro, was separately charged with contempt of Congress in June for refusing to appear for a deposition with the committee. Navarro’s trial is scheduled to begin in November.

The Justice Department opted not to charge two other Trump associates, Mark Meadows and Daniel Scavino, for defying the committee despite a House vote recommending it. Unlike Bannon, Meadows turned over some communications to the committee.

The committee could make multiple referrals to the Justice Department seeking criminal charges against Trump himself, according to its vice chair, Liz Cheney.

The main prosecution witness was Kristin Amerling, a top committee staffer who testified that Bannon spurned deadlines to respond to the September 2021 subpoena, sought no extensions and offered an invalid rationale for his defiance — a claim by Trump involving a legal doctrine called executive privilege that can keep certain presidential communications confidential.

The Justice Department charged Bannon last November after the Democratic-led House voted the prior month to hold him in contempt. Bannon separately was charged in 2020 with defrauding donors to a private fundraising effort to boost Trump’s project to build a wall along the U.S.-Mexican border. Trump subsequently issued a pardon to Bannon before that case could go to trial.

A pro-Trump mob stormed the Capitol and attacked police with batons, sledgehammers, flag poles, Taser devices, chemical irritants, metal pipes, rocks, metal guard rails and other weapons in a failed effort to block congressional certification of his 2020 election loss to Democrat Joe Biden.

The committee has said Bannon spoke with Trump at least twice on the day before the attack and attended a planning meeting at a Washington hotel. It played a clip of Bannon saying on his right-wing podcast the day before the attack that “all hell is going to break loose tomorrow.”

U.S. District Judge Carl Nichols limited the scope of the case Bannon’s team could present to the jury, moves that one of his lawyers said “badly stymied” the defense. Bannon was barred from arguing that he believed his communications with Trump were subject to executive privilege. He was also prohibited from arguing he relied on legal advice from an attorney in refusing to comply.

Bannon’s defense argued that he believed the subpoena’s deadlines were flexible and subject to negotiation between his attorney and the committee. In an 11th-hour reversal with the trial looming, Bannon this month announced a willingness to testify in a public hearing before the committee, an offer that prosecutors said did not change the fact that he had already broken the law.