"It puts a pit in your stomach and a weight on your chest that you can't just shake as something that's just kind of crazy," he said.
Out of an abundance of caution, he contacted the local police, who visited the school, recorded the message and began investigating.
It didn't take long to unearth the roots of the threat, preposterous as they were.
Two days earlier, on April 27, Comey had shared a tweet listing a handful of jobs he had held in the past alongside the hashtag #FiveJobsIveHad.
Hundreds of others had done the same before and since, but a small fringe group of conspiracy theorists seized on the tweet, claiming it contained a coded message.
By removing letters, the hashtag could be shortened to "Five Jihad," they argued. And a search for the abbreviation formed by the first letters of the jobs he listed — GVCSF — led to the Grass Valley Charter School Foundation, whose fundraiser was scheduled for this weekend.
Comey, they concluded, was broadcasting an attack, perhaps as a distraction from other pending news.
The Grass Valley police quickly determined that the theory was baseless and that the school, with about 500 students from pre-kindergarten through eighth grade, was under no threat.
"We definitely did our due diligence," Police Chief Alex Gammelgard said. "Every single potential piece we did pointed to the same thing: that it was not credible."
But word travelled fast in Grass Valley, which is home to about 13,000 people.
Maddock and Wendy Willoughby, president of the foundation, had started to hear from parents who were worried not about the predicted attack, but about the people who believed in it.
What if one of them showed up, armed, to protect against a threat that simply did not exist, as had happened at a popular Washington pizzeria two years ago? At the same time, some members of the community vowed to attend the event to provide protection.
After several sleepless nights, Maddock, worried the event could spiral out of control, announced last week that the fundraiser was canceled, as reported by The Sacramento Bee.
"This is an event with children's games, and activities and face painting, and a student art auction, and live music and food, and just a real community builder for us," he said. "I didn't want the flavour of the event to be suddenly tainted by people that were showing up for all the wrong reasons."
One of the first people to warn the school about the false conspiracy theory was Mike Rothschild, a researcher who had watched it gain steam online, its signal boosted by increasingly high-profile Twitter accounts.
"I saw it unfolding, and I recognised immediately how bad this could get," he said. "And ultimately it happened."
He had urged the school not to cancel the event for fear that those who believed in the conspiracy theory would claim victory (they did), but in the end Rothschild said he understood why officials made the decision they did.
Such theories have received much attention in the press during the past year or so, but they remain on the fringes, said Rob Brotherton, an assistant professor of psychology at Barnard College who has long studied conspiracy theories.
Giving them oxygen, even while debunking them, can nevertheless allow them to grow, he warned.
"It seems to me, having studied these things for a long time, that giving it this kind of platform, even when it's clearly framed as, 'This conspiracy theory is not true,' is only going to raise its profile," he said.
But Rothschild disagreed with that sentiment. "This is happening whether or not we write about it," he said. "The first time you encounter this should be poking a hole in it."
And fringe though they may be, online conspiracy theories can spiral out of control, resulting in real-world consequences, as was the case for the Grass Valley Charter School.
Not only was the community subjected to a minor panic because of the baseless conspiracy theory, but the school also missed out on an opportunity to raise about $15,000 and recoup thousands more that had been spent on the fundraiser, Paddock said.
Students suffered, too, Willoughby said. The theme for this year's fundraiser was "Save the Western Monarch Butterfly," and the event was to include a butterfly drawing contest with the submissions to be displayed at the festival, she said.
On Thursday, Willoughby gathered the submissions anyway, including one from a girl who had cut out her butterfly, pasted it onto a background and attached a piece of leather rope for it to hang up at the fundraiser.
"It's heartbreaking that these kids, that this is taken from them," Willoughby said.
Meanwhile, the online community that spread the false conspiracy theory to begin with has found a new subject to investigate, according to Rothschild.
"This stuff moves so fast," he said. "They've already moved on."
Written by: Niraj Chokshi
© 2019 THE NEW YORK TIMES
