A US judge barred Oath Keepers founder Stewart Rhodes from entering Washington DC without the court’s approval.
It comes after President Donald Trump commuted the far-right group leader’s 18-year prison sentence for orchestrating an attack on the US Capitol four years ago.
US District Judge Amit Mehta issued the order two days after Rhodes visited the Capitol, where he met with at least one legislator, chatted with others and defended his actions during a mob’s attack on January 6 2021.
Rhodes was released from a Maryland prison a day earlier.
Judge Mehta’s order applies to seven other people who were convicted of charges in the riot that halted the certification of Joe Biden’s 2020 presidential election victory over Mr Trump.
The order also prohibits them from entering the Capitol building or surrounding grounds without the court’s permission.
Rhodes was convicted of seditious conspiracy in one of the most serious cases brought by the Justice Department.
He was found guilty of orchestrating a weeks-long plot that culminated in his followers attacking the US Capitol in a desperate bid to keep Mr Trump, a Republican, in power.
Rhodes did not enter the building on January 6 and has said it was “stupid” that members of the Oath Keepers did.
“My guys blundered through doors,” he insisted during his visit to Capitol Hill earlier this week.
Mr Trump’s sweeping clemency order on Monday upended the largest prosecution in Justice Department history, freeing from prison people seen on camera viciously attacking police as well as leaders of far-right extremist groups convicted of orchestrating violent plots to stop the peaceful transfer of power after his election loss.
Mr Trump has defended the pardons, saying the defendants had “already served years in prison” in conditions he described as “disgusting” and “inhumane”.