Elon Musk Champions Twitter Fact-Checking Feature That Corrects Him

The new owner of the social-media platform has said he wants Twitter to be a free-speech zone but also a trusted source. “Twitter needs to become by far the most accurate source of information about the world,” Mr. Musk tweeted Nov. 6. “That’s our mission.”

Mr. Musk later tweeted: “When @CommunityNotes rolls out worldwide, it will have a powerful impact on falsehoods.”

Community Notes, after undergoing testing for more than a year, expanded to all users in the U.S. in early October. 

The information that surfaces through the notes is submitted by volunteers in a way similar to how Wikipedia works. Anyone can sign up to contribute to Community Notes as long as a verified phone number from a trusted U.S.-based phone carrier and proof of joining Twitter more than six months ago are provided. There can’t be any recent violations of Twitter rules.

Contributors can suggest a note on any tweet they think needs context, and a tweet can receive more than one. Before a note becomes public, other contributors are asked to rate it by answering the question “Is this note helpful?” with either “yes,” “no” or “somewhat.” 

To help avoid misuse of the system, each note is run through an algorithm that is maintained by Twitter, comparing it with other notes that are ranked as helpful by users with different points of view. “Notes need to be found helpful by people who have tended to disagree in their past ratings,” according to a blog post on Twitter’s website.

The notes that pass the algorithm are appended to tweets with a disclaimer that says: “Readers added context they thought people might want to know.”

Photos: How Musk Made Fortune

Since its expansion almost two months ago, Community Notes has added context to a plethora of tweets, including ones from the White House, Jimmy Fallon, The Wall Street Journal and Mr. Musk himself.

When Mr. Musk took over the platform, questions swirled among participants, with some using group chats to communicate with each other, about whether they should add notes to the new owner’s tweets if warranted, said Alec Palm, a frequent Community Notes contributor. 

“We all resoundingly decided yes, because Community Notes was built on the ideals that anyone can be fact-checked at any time,” said Mr. Palm, a 20-year-old college student. 

Mr. Musk tweeted a quote on Monday that he attributed to “Dune,” the science-fiction epic by Frank Herbert: “Fanaticism is always a function of repressed doubt.” A note was added underneath: “This is not a quote from the book ‘Dune’ but from the psychologist Carl Jung.”

Because Community Notes relies heavily on volunteers, the feature has been somewhat, though not entirely, insulated from the layoffs and other departures that have hit Twitter since Mr. Musk’s takeover. At least four of the eight employees who published a white paper about the Community Notes algorithm in October have left the company, according to their LinkedIn profiles. Twitter didn’t respond to requests for comment about the layoffs or Community Notes.

One concern about the program is whether enough people will volunteer to maintain it, said Karen North, a professor at the University of Southern California who focuses on social media. “You have to wonder who’s motivated enough to be a contributor that they’re willing to sign up and do that at this point,” she said. 

It couldn’t be determined exactly how many people contribute their time. During testing, the program had at least 2,500 contributors, according to the white paper. 

In recent weeks, Community Notes has weighed in on some high-profile issues.

After Mr. Musk reinstated the Twitter account of

Donald Trump

earlier this month, a YouTuber tweeted a screenshot of what appeared to be a tweet from the former president’s account. A Community Note was added that said: “Donald Trump did not tweet this and has not tweeted anything since his account was reinstated.”

Recently, the hashtag #RIPJimmyFallon started trending. After it went viral, Mr. Fallon, the host of “The Tonight Show,” tweeted: “Elon, can you fix this? #RIPJimmyFallon.” A Community Note underneath it cited an article from NBC and said: “Jimmy Fallon hasn’t passed away and he wants to make sure everyone knows it….The hoax seems to be part of an ongoing problem with imposter accounts tweeting misinformation on the platform.”

Four surveys run by Twitter between August 2021 and August 2022 while the feature was being tested found that a person who views a Community Note is on average 20% to 40% “less likely to agree with the substance of a potentially misleading tweet than someone who sees the tweet alone,” the company said.

Kate Klonick, a professor at St. John’s University’s School of Law, said it would take time for Twitter’s system to mature, pointing to Wikipedia’s processes that “took decades to define and refine.”

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Write to Meghan Bobrowsky at [email protected]