Heidi Beirich is a director at the Southern Poverty Law Center, the Montgomery, Alabama-based advocacy organization focussed on combating racism and bigotry. Beirich oversees the group’s Hatewatch blog and its print periodical, the Intelligence Report, which, each spring, publishes a comprehensive list of active hate groups. In April, 2014, Beirich got an e-mail, not the first, from an eighteen-year-old living in Tallahassee, Florida, named Jordan Jereb. He was pestering her about his own group, which he called the Republic of Florida. He included photos of his fellow white supremacists in action. He wanted to know why Beirich wasn’t paying any attention to them.

“You always ignore me and the ROF!” Jereb wrote, addressing Beirich by her first name. “You should be covering how extreme we are- I mean look at all these awesome pics- There simply are not that many out there of Militia’s that are this useful for your organization.” Jereb argued that the S.P.L.C. and the R.O.F. needed one another. “I mean honestly, who we ‘Market’ our ideas to and who you market your ideas to are 2 totally separate groups of people,” he wrote. “Can we just admit this is a symbiotic relationship in which that you get soccer moms worried for profit and I get teenagers involved in my political organization?” (The S.P.L.C. is a nonprofit group.)

But the R.O.F. did not appear to be large or effective enough for Beirich to worry about, despite Jereb’s marketing efforts. In October, 2013, the group’s YouTube channel had posted a four-minute video called “Silent Pack – Republic of Florida Special Operations Unit.” Four young white men in fatigues, helmets, and rebel-flag bandannas trudge down a residential lane as a white-power tune plays. They pause before a pruned hedge to pose with a “DON’T TREAD ON ME” flag. They hoist another flag in front of a Circle K gas station. They peer dramatically into a thicket of Spanish moss. No one seems to notice them. They stop to drink water and praise their leader—“That’s one badass guy,” the cameraman says—who is apparently elsewhere. As a reward for completing the march, the cameraman continues, the foursome will revisit the Circle K. “I ask that you keep it low-fat,” he tells the group, of the snacks its members will buy there. “This is what the new world order fears,” he says. “People like you. And people like me.”

“We try to avoid adding B.S. to our list,” Beirich told me on Friday. “They looked more like a militia for a long time than a hate group.” The Intelligence Report did run an article about Jereb in its Winter, 2014, issue, published in November of that year. Beirich and one of her colleagues agreed to meet with Jereb after his pestering e-mails. When they arrived in Tallahassee at the appointed time, Jereb was in the county jail, having been picked up on charges of trespassing at his old high school. The article deemed the R.O.F. “a would-be militia made up of kids barely old enough to buy guns.”

Further Reading New Yorker writers respond to the Parkland school shooting.

Last Wednesday, in Parkland, Florida, more than four hundred miles from Jereb’s home base, in Tallahassee, a nineteen-year-old named Nikolas Cruz allegedly killed at least seventeen people at Marjory Stoneman Douglas High School, injuring at least a dozen more, with an AR-15 semiautomatic rifle. The next day, the Anti-Defamation League reported that it had spoken with Jereb, and that he had confirmed that Cruz had trained with the R.O.F. Someone at the A.D.L. had spotted a thread on the notorious imageboard Web site 4chan, in which posters claimed that Cruz had associated with the group. It would later become evident that the purpose of the thread had been to fool members of the media. The idea for it reportedly originated, earlier that afternoon, on a chat app for gamers called Discord, which is popular with neo-Nazis.

“Nikolas Cruz was a revolutionary member of the Republic of Florida,” one post read, “who preached twisted and dark things like terrorism and attacking innocent people.” Purported pictures of Cruz attending R.O.F. gatherings also appeared. Jereb soon began receiving calls from reporters who’d found the R.O.F.’s “hotline” number on its home page. “He was part of our organization,” Jereb reportedly told the Daily Beast, about Cruz. “He wasn’t particularly active in it, but at some point he came to Tallahassee with I believe the Clearwater RoF. I know he didn’t live in Clearwater, but I think that was the company he clicked up with.” ABC News reported that three former schoolmates had said “that Cruz was part of the group. They claimed he marched with the group frequently and was often seen with Jereb.” These comments went well beyond what even Jereb had boasted. The sources for the ABC News report appear to have been some of the same online trolls who hatched the plan, on Discord, to trick the press. (ABC News declined to comment on its reporting; on Friday evening, the story was removed from its Web site.)

Inadvertently or otherwise, the trolls on 4chan were not entirely wrong: on Friday, CNN reported that, in a private Instagram group chat to which CNN had gained access, Cruz had frequently “talked about killing Mexicans, keeping black people in chains and cutting their neck.” The Daily Beast, in its story about Cruz’s alleged ties to the R.O.F., also highlighted anti-Muslim slurs that Cruz posted on a previously public Instagram account, and quoted actual former classmates, on the record, who said that Cruz often made racist comments. It is not clear what role these beliefs may have played in the Parkland shooting. But it is increasingly clear that Cruz’s supposed connection to a tiny hate group in north Florida is almost certainly a fiction.

“You have to be skeptical, like we are with international terrorists and terrorist groups,” Beirich told me on Friday by phone, as the story of Cruz’s affiliation with the R.O.F. began to unwind. Until you have proof, you really shouldn’t write about connections individuals may have to hate groups. I think Jordan was cynically using this opportunity to get himself in newspapers across the country.”

Unable to reach Jereb by phone after he’d ceased Thursday’s media blitz, I sent an e-mail to R.O.F.’s e-mail address, which is posted on its Web site. I asked Jereb how he’d managed to fool much of the media. Just before ten o’clock on Friday night, I received a reply. “Technically,” the e-mail read, “I was tricked too, I just played along once I realized ADL was helping the 4chan trolls shill the story.” Early Saturday morning, I got another message, which claimed that the media coverage had attracted “new potential recruits. We may be able to double, Perhaps almost tripple our numbers.” The message went on, “There is even a woman trying to join us based on what she saw on TV. So I guess we have properly ‘exploited’ this tragedy, Or more accurately, Benefited from the medias exploitation of it.”

Next Wednesday, a week after the Parkland shooting, the S.P.L.C. will unveil its updated hate-group list. The Republic of Florida is on it.