Steve Bannon, a former Trump advisor, has been charged with contempt of Congress for his refusal to testify on the incident at the US Capitol.
He was called to speak about what he knew of the protest’s plans, which culminated with the storming of Congress.
The Justice Department decided on Friday to bring charges against Mr. Bannon, 67 after the House of Representatives voted last month to refer the case to it.
He might spend up to a year in jail and pay a fine of $100,000 (£74,500).
As senators gathered to confirm the election results on January 6, Trump supporters broke into the US Congress building.
This was the first such charge to result from the investigation conducted by the House of Representatives Select Committee into the Capitol complex invasion on January 6.
Two counts of contempt have been filed against Mr. Bannon: one for failing to appear for a deposition and the other for failing to provide the committee with requested materials.
The political adviser, who was expelled from the White House in 2017 but continued to support the former president, is anticipated to turn himself into police on Monday and appear in court.