Former campaign adviser for President Donald Trump, Roger Stone walks out of the federal courthouse following a hearing, Friday, Jan. 25, 2019, in Fort Lauderdale, Florida. Credit: Lynne Sladky | AP

Roger Stone has said he intends to plead not guilty at a federal court appearance set for Tuesday in Washington, where the longtime friend and adviser of President Donald Trump faces criminal charges in special counsel Robert Mueller’s investigation of Russian interference in the 2016 U.S. election.

Stone was indicted last week and accused of seeking to gather information about hacked Democratic Party emails at the direction of a senior unidentified Trump campaign official before the 2016 election and then lying about it to Congress.

At an initial court appearance Friday in Florida after his arrest at his Fort Lauderdale home, the 66-year-old Stone appeared in shackles but was released on $250,000 bond.

He is due for an 11 a.m. arraignment Tuesday before U.S. Magistrate Deborah Robinson in Washington after spending the weekend in a media blitz in which he proclaimed his innocence, criticized prosecutors and promised not to testify against the president.

He faces charges of lying, obstruction and witness tampering.

Stone, a veteran GOP operative and friend of Trump for four decades, briefly advised the presidential campaign in 2015 and remained in contact with Trump and top advisers through the election.

The indictment centers on Stone’s alleged efforts to learn when potentially damaging internal emails from Hillary Clinton’s presidential campaign would be released by Julian Assange, WikiLeaks’s leader.

U.S. authorities in July indicted a dozen Russian military intelligence officers on charges they hacked Democrats’ computers, stole their data and published those files to disrupt the 2016 election, using as one of their conduits WikiLeaks, the global anti-secrecy group, which publicized the emails during the campaign’s final months.

In Stone’s indictment, prosecutors charged that after the initial July 22, 2016, release of stolen emails, “a senior Trump campaign official was directed to contact Stone about any additional releases and what other damaging information Organization 1 had regarding the Clinton campaign.” The indictment does not name the campaign official or who directed the alleged outreach to Stone.

The indictment states that Stone thereafter told the campaign about potential future releases by “Organization 1,” which people familiar with the case said is WikiLeaks.

Stone has given scores of interviews during the months that he’s been under investigation and preempted prosecutors by publicly releasing many of the emails and texts he knew they were examining before they could be used in legal action.

On social media since his arrest, Stone all but invited a federal judge to impose a gag order, saying a directive to mute him is “the fervent wish of the Deep State.”

Stone got his start in politics working for Richard Nixon’s 1972 reelection campaign and has a tattoo on his back of the disgraced ex-president. Since then, he has advised Republican and Libertarian candidates, including Ronald Reagan, Bob Dole and Gary Johnson.

After a formal entry of a plea before the federal magistrate, Stone’s case will go before U.S. District Judge Amy Berman Jackson of the District of Columbia for a scheduling hearing, expected as soon as Thursday.

In other Mueller cases assigned to her, Jackson – a former federal prosecutor, white-collar defense attorney and 2011 appointee of President Barack Obama – has not been reluctant to rein in attorneys and parties whose out-of-court comments she found likely to lead to pretrial publicity that might taint a jury or jeopardize a fair trial.

Jackson issued a gag order days after an attorney for former Trump campaign chairman Paul Manafort gave a statement outside the federal courthouse attacking the special counsel investigation and defending his client to reporters in November 2017.

Stone has repeatedly denied any contact with Russia or WikiLeaks. He has said he had no advance knowledge of what material WikiLeaks held, adding that predictions he made about the group’s plans were based on Assange’s public comments and tips from associates.

Stone and WikiLeaks and Assange have said they never communicated with one another.

The seven-count indictment against Stone asserts that after the election, he lied in congressional testimony about his activities and efforts to learn about the release of potentially damaging emails and that he attempted to persuade another witness, identified only as “Person 2,” to refuse to talk to the House Intelligence Committee.

People close to the case said Person 2 is New York comedian Randy Credico. A lawyer for Credico, Martin Stolar, has declined to comment.

The Washington Post’s Devlin Barrett, Rosalind S. Helderman, Lori Rozsa and Manuel Roig-Franzia contributed to this report.