Robert Barnes has been a reporter and editor at The Washington Post for more than 30 years. For the past 12, he has covered the Supreme Court.

This week he experienced something he says was a first in his career: a storm of commentators, many anonymous, swarming his social media accounts and email inbox to tell him that something he saw with his own eyes and reported in The Post did not actually happen: Justice Ruth Bader Ginsburg, alive and well, attending a performance about her life at a museum in Washington — her first public appearance since she underwent cancer surgery in December.

A falsehood has been spreading in dark corners of the Internet that Ginsburg is dead — and in the hours after Barnes published his report, conspiracy theorists pelted him with their doubt-mongering. Photos were not allowed at the event, so one of the doubters emailed Barnes 21 questions about Ginsburg’s appearance — the size of her security detail, what gender they were, for example — telling Barnes that if he did not answer every single one of them, it would be a sign his article was not to be believed.

Ginsburg did not attend the State of the Union on Tuesday night. Neither did Justices Clarence Thomas, Samuel A. Alito Jr., Sonia Sotomayor or Stephen G. Breyer, but the conspiracy theory that Ginsburg is dead may draw more oxygen from the 85-year-old justice’s absence.

Conspiracy theories about political figures are not new, but social media and other digital tools that allow for and, at times, encourage their wide dissemination have given them new prominence in the Trump era. Though it is impossible to know how large these groups are, the disruption they cause far exceeds their size, in part because of the visibility that social media algorithms lends to assertions that fire people up, regardless of the veracity of those claims.

But there is often more to these movements than is first apparent.

[The world’s oldest person record stood for decades. Then came a Russian conspiracy theory.]

QAnon, the shorthand for a tale that fantasizes about a vast “deep-state” conspiracy aimed at thwarting President Trump, was presented as an organic movement when it burst into mainstream consciousness over the summer. But reporting later showed that some of the main groups that had spread it were profiting from the attention it helped bring to them.

The Pizzagate conspiracy theory spread through the fringes of right-wing Internet culture to Twitter, where it was amplified by people with huge followings — and also, as it turns out, Russian bots. And the conversation after major news events, such as the Parkland shooting in Florida last year, is routinely distorted by complex processes that lend themselves to gaming and manipulation, experts say, though specific actors and motivations can be hard to discern immediately. They include spurious accounts, trending hashtags supported by bot networks, and opaque algorithms that highlight buzzy content and commentary — no matter what the facts are.

Two anonymous Twitter accounts were behind the edited snippet of video about an encounter between a group of Catholic high school boys and a Native American activist that went viral, for example. One of the accounts was later booted from Twitter after the service said it was manipulating the conversation.

In Ginsburg’s case, questions about her health began to spread around the time she missed the court’s first case, Jan. 7, as she was recovering from surgery she had on Dec. 21. It appears to have originated on the message boards that house the QAnon theory. An anonymous but influential account posted a stew of doubt-mongering, wondering about Ginsburg’s “real medical diagnosis” and wondering what kind of “off-market drugs” were sustaining her.

“The clock is ticking,” the commenter wrote. “PANIC IN DC.”

There was no panic in D.C.

The mini empire of amplifiers, profiteers and fame seekers benefiting from QAnon’s small but passionate audience went to work. Soon, videos questioning the official line on Ginsburg’s health were the top search results for the justice’s name on YouTube. An online petition to impeach her failed to meet a 5,000 signature goal.

But its real boost came when a couple of right-wing personalities with large social media followings engaged it. Ben Garrison, a prominent pro-Trump cartoonist, tweeted about Ginsburg’s whereabouts, musing on his blog about whether liberals would ever keep her death “a secret,” so Trump couldn’t fill the seat with a conservative.

The Fox News show “Fox & Friends” briefly aired a graphic indicating that Ginsburg had died, then quickly apologized. James Woods, an actor who is a mainstay of the conspiracy-laden parts of the pro-Trump Internet, helped get the hashtag #WheresRuth trending on Twitter on Jan. 28. Two days later, Sebastian Gorka — a former adviser of President Trump’s — tweeted “Still no sign” to his 700,000 followers, noting the State of the Union was about a week away.

And then the theory started to draw mainstream coverage — another way that conspiracy theories spread, even when they are properly fact-checked, debunked and contextualized, experts say. And the Twitter hoaxes continued. An anonymous account shared an old photo of the presidential hearse carrying Ronald Reagan’s body past the U.S. Capitol, writing “Prominent DC Funeral Home vehicle seen leaving the Ginsberg estate . . . what’s going on?”

[How a star chef’s angry MAGA-hat tweet triggered a storm of misleading news]

The conspiracy theory lives on in the algorithms.

YouTube is still recommending “RGB dead” as one of its autofill searches. Twitter’s autofill recommendations for “RBG” have an even wider selection: “#RBGWhereYouBe,” “#RGBProofOfLife” and “RBG dead.”

If hoaxers were seeking attention for the theory, they certainly have succeeded. Targeting reporters such as Barnes who have wide followings online is a good way to start. Other reporters who saw Ginsburg on Monday night at the performance were hit with the same flood of replies and emails.

After the Parkland shooting, Whitney Phillips, a Mercer University professor who studies online culture, told The Post that conspiracy theorists and hoax spreaders are “really good at seeding a story with an establishment outlet so they can bring that prize back to those far-right circles.”

People know that journalists are on Twitter, searching for news and story ideas. It is considered a victory when those fringe conspiracies are amplified into the mainstream by a reporter who is trying to debunk them. After the QAnon theory went viral, for instance, conspiracy theorists were delighted by the mainstream attention.

The Supreme Court has been the target of conspiracy theories before. After Justice Antonin Scalia died suddenly at a Texas ranch in 2016, conspiracy theories swirled about the nature of his death, and whether he was murdered as a political hit. The theories, which have no grounding in evidence, live on today.

The Supreme Court doesn’t have another public session until Feb. 19, Barnes said, noting that specialists said there’s a six- to eight-week recovery typically expected for the procedure Ginsburg had undergone.

“It seems logical that she would be back for it,” he said.

Barnes said he is less offended by the suggestion that he was fooled by a body double than that he made up Ginsburg’s appearance Tuesday night.

“Feeling grateful for tweeters who say I, and many others, saw RBG body-double, as opposed to those who think I lied,” he wrote on Twitter. “They won’t be happy if she skips speech tonight, as she has Trump’s first 2. Thomas and Alito not likely either, but, I swear, also alive.”

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