Hardly a day goes by without Elon Musk amplifying fake news or conspiracy theories on X, formerly Twitter, a platform he once said “needs to become by far the most accurate source of information about the world.” But some of his false claims over the summer have prompted a new lawsuit against the tech CEO from a young man who says he found himself the target of a far-right harassment campaign.

On June 24, as the city of Portland celebrated Pride Night, two right-wing extremist groups that had turned out to intimidate the LGBTQ community in attendance instead wound up turning on each other. The Proud Boys, a militant gang whose members have been receiving stiff jail sentences for their role in the Jan. 6 Capitol riot, encountered the Rose City Nationalists, who openly espouse neo-Nazi ideology. Bad blood between the two factions over strategic and personal disagreements led to an all-out street brawl, and Proud Boys were able to unmask a pair of RCN members in footage that later went viral.

Immediately, anonymous far-right accounts invested in downplaying Nazi violence began to sow the seeds of a familiar conspiracy theory: the RCN weren’t an actual Nazi gang but federal agents posing as such in a “false flag” operation. Musk had proven susceptible to this kind of phony narrative before, expressing doubt the previous month that a mass shooter covered in Nazi tattoos who killed eight in Allen, Texas, was a white supremacist, wondering if the massacre was a “bad psyop.” In this case, a troll on X affiliated with the white nationalist “groyper” scene falsely identified Ben Brody, 22, a recent graduate of the University of Riverside, California, as one of the RCN brawlers who had his mask ripped off. They shared a picture of Brody from the Instagram account of his Jewish college fraternity, Alpha Epsilon Pi, which identified him as a political science major planning to pursue a career in government.

The implication was that Brody — who had been in California during the Portland Pride Night event — was part of a scheme by a federal agency to stoke fears of right-wing extremist violence. The theory was based on nothing more than a slight resemblance between Brody and the man in the video. But that, it seems, was enough for Musk, who started replying to X users spreading Brody’s name and likeness in this dangerously misleading context. “Very odd,” Musk tweeted of Brody’s supposed involvement on June 25. The next day, even after many on the site had warned Musk that he was falling for misinformation, he replied to a crypto influencer who shared the same false accusation — that Brody was among a number of feds “Planting Fake Nazis at Rallies.” Musk wrote in response, “Always remove their masks.”

According to Texas firm Farrar & Ball attorney Mark Bankston, Brody’s legal counsel, these two comments did not rise to the level of defamation. (Bankston previously represented two Sandy Hook parents in a suit against conspiracy theorist Alex Jones, winning them $45 million in damages over his claims that the school shooting never happened.) Instead, in his complaint on Brody’s behalf in and a thread on X explaining the case, Bankston wrote that Musk crossed a line when, on June 27, he replied to ZeroHedge, a financial blog known to dabble in right-wing conspiracism. “Patriot Front ‘White Supremacist’ Unmasked As Suspected Fed,” read the title on the link shared by ZeroHedge, which led to a blog post that included a tweet from someone repeating the false accusation against Brody.

“Looks like one is a college student (who wants to join the govt) and another is maybe an Antifa member,” Musk replied, clearly referring to Brody, “but nonetheless a probable false flag situation.” He also tagged Community Notes, X’s crowdsourced system, for fact-checking content on the platform. While ZeroHedge’s tweet has since been deleted, Musk’s reply remains visible.

As the smear against Brody began to take hold, he made desperate efforts to clear his name: On June 26, he recorded a video on Instagram denying that he had anything to do with the Portland fight, providing debit card receipts and time-stamped security footage from a store that confirmed he was in California that day. Of those who informed Musk that Brody was not the man in the Portland video, several included a link to his debunking of the story on Instagram — to no avail, as Musk committed to a false narrative when he replied to ZeroHedge the following day. He also ignored warnings that his posts could lead to Brody being directly threatened.

Despite his lawyers being informed of Brody’s defamation claim in August, Bankston has said that Musk has declined to either retract his unfounded accusation or apologize for it. Musk did not respond to Rolling Stone‘s request for comment.

Brody and his family were doxxed as a result of the conspiracy theory Musk promoted on his site, Bankston tweeted on Monday, and had to flee their home during “weeks of terror.” Brody, he wrote, has a reputation now “catastrophically damaged” by the wealthiest man on the planet and has suffered mental anguish “at the crucial moment when he exits college and enters his career path.”

The defamation suit catalogs various episodes of Musk’s untruthfulness on social media, including the infamous 2018 tweet claiming he had secured funding to take Tesla private at $420 a share (he and Tesla both had to pay $20 million in SEC fines for the false statement) and when he last year shared a bizarre fake news article alleging that a man who broke into the San Francisco home of then-House Speaker Nancy Pelosi and attacked her husband Paul Pelosi with a hammer was a hired sex worker known to Paul.

The suit also acknowledges another defamation suit brought against Musk for his reckless tweets — this one brought by Vernon Unsworth, a British cave diver who, in 2018, roused Musk’s ire by criticizing a submersible the billionaire had brought to Thailand for potential use in the rescue of a youth soccer team trapped in a flooded cave system. Musk called Unsworth a “pedo guy” in a tweet, later answering another user who called him out for the smear, “I bet ya a signed dollar it’s true.” During the subsequent suit, Musk contended that he had only meant “pedo guy” as an insult, not a statement of fact. Unsworth, represented by former attorney Lin Wood, who is now better known for his QAnon beliefs and filing frivolous legal challenges in attempts to overturn the 2020 election results and restore Donald Trump to the White House, went on to lose the case.

With his win against conspiracy kingpin Alex Jones, Bankston has a somewhat better track record and sees the new suit as a way to check Musk’s increasingly irresponsible behavior. Brody, he tweeted Monday, “is undeterred” by the prospect of facing the CEO in a legal setting. “He understands that a lawsuit is the only way he will be able to truly clear his name or change Musk’s behavior,” Bankston wrote. “He is unbelievably brave to take on this challenge.”

Musk, for his part, has been busy posting anti-vaxxer memes and insights like “Pronouns in bio means the woke mind virus ate your brain” while still finding the time to get in a spat with the nation of Germany over their humanitarian efforts to save migrants traveling across the Mediterranean Sea. All in a day’s work, surely.