WASHINGTON — A federal judge on Tuesday ordered President Trump’s former adviser Roger J. Stone Jr. off social media, declaring that he violated a gag order by using Instagram and other platforms to attack the special counsel’s investigation and officials tied to it.
Mr. Stone, a self-described dirty trickster, is awaiting trial in November on charges related to his attempts to communicate with WikiLeaks about stolen Democratic emails during the 2016 election campaign. The special counsel, Robert S. Mueller III, secured the indictment against Mr. Stone.
Judge Amy Berman Jackson of the United States District Court in Washington had placed Mr. Stone under a gag order in February after he posted a photo of her with an image of cross hairs on Instagram. Judge Jackson warned Mr. Stone at the time that if he violated the terms, she would send him to jail.
“My order was as clear as day,” she said on Tuesday in determining that he was in breach of it, though she did not revoke his bail. The new conditions ban Mr. Stone from writing his own posts on Facebook, Instagram and Twitter or using his accounts to disseminate others’ material. Twitter kicked off Mr. Stone in 2017 after a series of incendiary posts.
She cited nearly a dozen apparent violations of the order, many of which were Instagram posts that appeared like memes. One called the former C.I.A. director John Brennan a traitor; another claimed Mr. Stone’s indictment was invalid because the Russia investigation was a hoax; a third mocked Representative Adam Schiff, Democrat of California, who heads the House committee that had sought Mr. Stone’s testimony.
The punishment is a blow to the legal strategy of Mr. Stone, who has been prolific on social media and used it to raise money for his defense. He has more than 50,000 followers on Instagram, and he regularly posts with the hash tag “#rogerstonedidnothingwrong.”
Mr. Stone has also published a book about his defense, “The Myth of Russian Collusion: The Inside Story of How Donald Trump REALLY Won” and accused Mr. Mueller in an Instagram post of using investigative tactics “straight out of the Gestapo’s playbook.”
Prosecutors from the United States Attorney’s Office in the District of Columbia, who took over the case after Mr. Mueller wrapped up his inquiry, have argued that Mr. Stone’s actions could bias the jury pool and threaten the government’s ability to conduct a fair trial.
“I have twice given you the benefit of the doubt,” the judge said. But while he promised to scrupulously abide by her narrowly tailored order, she said, he had deliberately used social media to fan publicity about his case.
She said his lawyer had to “twist himself into a pretzel” in vain attempts to defend him.
His lawyers argued that he was exercising his constitutional right to free speech. “None of these are the kinds of things that have any reasonable basis for suggesting that they would affect a fair trial,” Bruce S. Rogow, one of his lawyers, said.
Jonathan Kravis, an assistant United States attorney, told the judge that the government was not asking her to fine or sanction Mr. Stone for violating her order. Instead, he asked Judge Jackson to specify the breadth of her order, clarifying that it covers comments about public filings in his case, photographs, and comments posed as questions attached to material posted by others.
He also suggested that the judge consider prohibiting Mr. Stone from using any form of social media. “No matter how clear a line the court draws the defendant will cross it and then will try to come to court and argue that he can’t be held responsible because there was some ambiguity,” he said.
Prosecutors have said that a top Trump campaign official dispatched Mr. Stone to obtain information from WikiLeaks about the hacked Democratic emails, which were stolen by Russian operatives and released during the campaign to damage Mr. Trump’s opponent, Hillary Clinton.
The indictment of Mr. Stone, which did not identify the campaign aide, underscored the campaign’s eagerness to benefit from the stolen emails. The theft of the emails from Mrs. Clinton’s campaign chairman and from Democratic political organizations was one of Russia’s main pillars of attack in its plot to sabotage the American presidential race.