Former Trump strategist Steve Bannon has been charged with contempt of Congress after refusing to testify about the US Capitol riot on 6 January.
Steve Bannon has not publicly commented on Tuesday's vote in the House Select Committee. Photo: AFP
The right-wing media executive had been summoned to testify about what he knew about plans for the riot.
His lawyers argued that his communications involving the former president were protected.
Bannon, 67, could now face up to a year in prison and a $US100,000 fine.
The political advisor - who was fired from the White House in 2017 but remained loyal to Donald Trump - is expected to surrender to authorities on Monday, when he will be arraigned in court.
This is the first such indictment to come out of the committee's probe of the 6 January invasion of the Capitol complex.
One of the contempt counts against Bannon is linked to his refusal to appear for a deposition and the other is for his refusal to produce documents for the committee.
Trump supporters stormed the US Congress building on 6 January as lawmakers were meeting to certify the election result.
Trump, a Republican, has refused to acknowledge losing the election to Democratic President Joe Biden last year, making claims - without evidence - of mass voter fraud.
Lawmakers are considering similar contempt charges against Trump's former chief of staff Mark Meadows, who also refused to comply with a subpoena.
In a statement released on Friday, US Attorney General Merrick Garland said the indictment reflected the justice department's "steadfast commitment" to the rule of law.
Subpoena documents quote Bannon as saying on his radio show the day before the riot that "all hell is going to break loose tomorrow".
But Trump had urged his former aides to reject all requests to testify. He argued they have the right to withhold information because of executive privilege - a legal principle that protects many White House communications.
The US Court of Appeals in Washington is scheduled to hold a hearing at the end of this month to rule on Trump's claim of executive privilege, after it was rejected by a lower court.
The former president is also attempting to block a trove of phone records, visitor logs and other White House documents that congressional investigators are chasing for their Capitol riot inquiry.
The Democratic-controlled House voted mostly along party lines last month to send the case to the justice department for possible prosecution. The move effectively transferred control of the matter under the department's purview.
Before leaving office in January, Trump pardoned Bannon of charges that he had defrauded donors who gave money to fund construction of a southern border wall.
Contempt of Congress cases are notoriously difficult to litigate - the last time such a prosecution took place was in 1983 against a Reagan administration official.
Both Attorney General Eric Holder and Internal Revenue Service official Lois Lerner of the Obama administration were held in contempt of Congress by lawmakers in 2012 and 2014 respectively, but neither was criminally charged.
- BBC