If President Donald Trump ends up pardoning his former political operative Roger Stone, it could very well be—at least in part—thanks to the sustained efforts of a Fox News star and part-time Trump adviser: Tucker Carlson.

For roughly a year, the primetime host has done a series of segments devoted to calling on the president to pardon the so-called “dirty trickster” Stone, a Republican consultant, Nixon enthusiast, and lobbyist who had long advised Trump.

The show’s position as a platform for pro-Stone messaging is potent enough that Trump allies who seek leniency for Stone have specifically sought to appear on the Fox News show in order to get the message to the president.

Stone’s situation has, of course, been of personal interest to the president for a while now. On multiple occasions over the past year, Trump, during casual conversation with White House aides and close associates, has brought up—unprompted—recent episodes of Tucker Carlson Tonight. Trump would then quickly note that Carlson did a segment or monologue on Stone’s predicament, and then ask his aide or friend if they’d seen the episode and “What do you think?” according to two sources with direct knowledge of the president’s private comments on the matter.

“That’s how he [often] talks, not showing his hand. He’ll say, ‘What do you think about’ this or that, which will be often code for ‘I’m interested or looking into doing’ this,” one of these people said.

On Tuesday, all four prosecutors handling Stone’s court case withdrew, mere hours after the Justice Department headquarters intervened to supercede their recommendation to a federal judge that Stone be sentenced to seven-to-nine years behind bars. And on Wednesday morning, Trump tweeted, “Congratulations to Attorney General Bill Barr for taking charge of a case that was totally out of control and perhaps should not have even been brought.” The president also posted a tweet railing against the “rogue” prosecutors, branding them part of “the swamp,” and tagging Carlson and Fox & Friends at the end.

And it’s a topic Carlson has fervently taken up as a cause célèbre.

Off-camera, Carlson has at times moonlighted as an informal adviser to Trump. Last year, he privately lobbied Trump against military action on Iran and also used their private chat as an opportunity to trash the president’s more hawkish senior officials, including Secretary of State Mike Pompeo and now-former National Security Adviser John Bolton. On-camera, Carlson helms a program that this president regularly tunes into, with Trump identifying with the host’s immigration-restrictionist, culture-warrior themes.

Since early last year, Carlson has been offering up a steady stream of segments framing Stone as a victim of anti-Trump law-enforcement run amok and explicitly advocating for the president’s intervention.

One of Carlson’s recurring on-air guests to discuss a potential Stone pardon has been Michael Caputo, another former Trump adviser and a close friend of the Stone family. Asked if he’s appeared on Carlson’s show specifically because he safely assumed Trump would see it, Caputo told The Daily Beast on Tuesday night, “Yes, that was my intention. Tucker has longer segments where he makes convincing arguments about issues the president’s base cares about. Nobody knows that better than the president. It’s a no-brainer.”

During Carlson’s broadcast Tuesday night, the Fox News primetime star directly appealed to the president and called for clemency for Stone. Expressing concern that the notorious political trickster could “die in prison,” Carlson described Stone as a “67-year-old man with no criminal record” who was caught up in the “Russia hoax.”

Claiming violent criminals get far more lenient prison sentences than Stone’s recommended sentence of seven-to-nine years, Carlson grumbled that the left and CNN want the ex-operative to rot in jail, adding, “This man needs a pardon.”

Carlson’s demand for clemency as Stone stares down prison time is the culmination of the Fox host’s prolonged effort to clear his buddy. Prior to his indictment as a result of the Mueller investigation, Stone repeatedly appeared on Carlson’s show in 2018, calling the special counsel’s probe “Orwellian” at one point while claiming Robert Mueller was persecuting him for supporting Trump.

After Stone was eventually charged with obstruction, witness tampering, and lying to Congress in early 2019, Carlson’s on-air campaign to help secure a pardon for the longtime Trump confidant began in earnest, hosting the Trump ally the day of his Jan. 25 arrest to rail against the indictment.

Days after the Stone raid, meanwhile, Carlson fumed, “Mueller himself is a threat to our democracy,” grousing that “nobody controls” him and the “all-powerful unelected prosecutor” was able to “send armed men to your home to roust you from bed at gunpoint just because he feels like it.” The Fox host also began peddling a discredited conspiracy that Mueller tipped off CNN on Stone’s raid in order to capture the whole thing on camera.

Weeks later, after Stone was placed under a full gag order, following inflammatory social media posts that the judge in the case deemed threatening, Carlson and his guests began openly calling for his pardon.

“Roger Stone is facing life in prison,” Carlson declared on his March 22 broadcast. “He was indicted by an investigation designed to find collusion, indicted on minor charges. He was dragged from his own home in a morning FBI raid. They put an amphibious vehicle outside his house and pointed an automatic weapon in his face, all to find collusion. But there was no collusion. Stone is still looking at life in prison. Where is Roger Stone's pardon? His pardon from the president? Let's hope it comes very soon.”

A few days later, Caputo advised Trump through the TV set to issue clemency for Stone via Twitter.

“Pardon General Flynn. Pardon George Papadopoulos. And pardon Roger Stone right now, Mr. Trump,” Caputo exclaimed on Tucker’s March 27 show. “Don’t wait until after the election, they deserve it now. Do it right now,” he added. “Do it right now on Twitter.”

Caputo and Carlson circled back to this topic in May, with Carlson telling the former Trump aide that “it would be nice to see some pardons, a pardon of Roger Stone, to begin” with.

Following Stone’s guilty verdict in November, Carlson once again called for Trump to give the conservative operative a pardon, reminding the president that he had called the decision against Stone a “travesty” while criticizing reports that Trump’s inner circle was advising him against getting involved.

While hosting Stone’s daughter Adria Stone, who pleaded with the president to “save” her family, Carlson noted that Trump had recently pardoned two others and “signed a law not that long ago that, in effect, pardoned a lot of crack dealers and also some rapists.”

“I honestly do think that after watching a series of people, some of whom are not deserving at all, get pardons from this White House, in effect or literally, you know I think people are going to be watching really carefully to see if your dad is pardoned,” Carlson concluded. “I'm going to be, that's for sure.”

In the meantime, figures like Carlson are likely going to be the public voice and face of Stone’s case far more than Stone himself will be. Reached for comment on this story Wednesday afternoon, Stone simply messaged back, “I am under a gag order and therefore have no comment.”

—With additional reporting by Max Tani.