Who is Roger Stone, the Trump ally in the January 6 panel’s crosshairs?

At its hearing on Capitol Hill on Thursday, the House January 6 committee is expected to show footage of Roger Stone, shot by Danish film-makers.

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According to the Washington Post, the clips will show that Stone “predicted violent clashes with leftwing activists and forecast months before the 2020 vote that [Donald Trump] would use armed guards and loyal judges to stay in power”.

CNN said footage also showed Stone the day before election day saying: “Fuck the voting, let’s get right to the violence.”

So who is Roger Stone?

A Republican strategist, consultant and author, he is most often described as a self-confessed political dirty trickster and longtime Trump adviser, given to flamboyance in tailoring and swinging as well as campaign stunts.

Now 70, Stone started out as a student volunteer on Richard Nixon’s re-election campaign in 1972, “pulling … penny-ante tricks” against Democrats or, in the Nixonian vernacular, “ratfucking” the president’s opponents.

Before Nixon’s downfall in 1974, amid the Watergate scandal, Stone worked for the Committee to Re-elect the President, or Creep.

After Nixon, Stone – who has a tattoo of the 37th president on his back – worked with Paul Manafort and Charles Black to build a Washington lobbying firm that flourished in the 1980s, often representing clients other firms might have found unsavoury.

Mobutu Sese Seko, the president of Zaire, was one. Donald Trump was another.

Stone advised Trump during his flirtation with a presidential run in 2000. In the presidential election the same year, Stone played a prominent role in stopping a recount in Florida, thereby securing the White House for George W Bush. In the mid-2000s, Stone was involved in the downfall of Eliot Spitzer, a Democratic New York governor who used prostitutes.

Stone was back at Trump’s side in 2015, when he finally ran for president. Stone was fired or resigned but remained in Trump’s orbit, an erratic asteroid endangering anyone in his path, during the billionaire’s campaign and time in power.

In 2019, Stone was indicted by Robert Mueller, the special counsel investigating Russian election interference and links between Trump and Moscow.

Stone was convicted on seven counts of lying to Congress, obstruction of justice and witness tampering, in relation to his links to Trump’s campaign and to WikiLeaks, which released Democratic emails obtained by Russian hackers.

In February 2020, prosecutors recommended Stone be sentenced to between seven and nine years in prison. After Trump complained by tweet, the Department of Justice intervened, saying the recommendation was too harsh. Four prosecutors resigned in protest.

Stone was sentenced to 40 months in prison but never went to jail. In December 2020, in the midst of Trump’s attempt to overturn his election defeat by Joe Biden, Trump granted Stone clemency.

In Trump’s attempt to overturn the election, Stone denies working with far-right groups including the Oath Keepers and the Proud Boys around the Capitol attack. But last week, such links came up at the start of the trial of the Oath Keepers leader, Stewart Rhodes, on seditious conspiracy charges.

Related: Trump ally Roger Stone: Americans can now choose ‘alternative’ truths

Randall Eliason, a former federal prosecutor who teaches law at George Washington University, told the Washington Post: “It seems like the prosecution is treating Stone as an un-indicted co-conspirator.”

Stone’s decision to allow documentary film-makers to follow him in his efforts to “Stop the Steal” was characteristic – and landed him in characteristic trouble, in the sights of the January 6 committee and the justice department. Summoned to appear before January 6 investigators, Stone repeatedly invoked his fifth-amendment right against self-incrimination.

Stone has recently teamed up with Michael Flynn, a retired general, ex-national security adviser and leading pro-Trump plotter.

In July, Sean Morales-Doyle, a Brennan Center expert on voting rights and elections, told the Guardian Stone and Flynn’s attempts to train Republican canvassers and poll watchers were “a sham, aimed … at undermining public faith in our elections and setting the stage for future attempts to subvert the will of the people”.