A conspiracy theory alleging Democratic presidential nominee Joe Biden would secretly wear an earpiece during the presidential debates had been circulating throughout September on social media platforms and far-right message boards before President Donald Trump’s campaign and Fox News amplified it.

On September 29, Fox News published an article that Trump’s campaign wanted “a third party to inspect the ears of each debater for electronic devices or transmitters” and that Biden’s campaign had declined. The narrative was then amplified in multiple Fox segments and elsewhere in right-wing media, as well by “Q” -- the central entity of the QAnon conspiracy theory.

This conspiracy theory had been circulating throughout September on both social media platforms and far-right message boards, according to a Media Matters review.

A search on CrowdTangle, an analytics tool owned by Facebook, found thousands of engagements combined on posts pushing the earpiece conspiracy theory on Instagram pages, Facebook pages, and Facebook groups -- including groups focusing on QAnon.

On Twitter, Juanita Broaddrick received more than 10,000 retweets on a September 21 tweet urging someone to “check Biden’s ears before the first debate.”

Days later, Michael Coudrey, a known conspiracy theorist, tweeted that Biden uses “a specialty designed earpiece so he can recite whatever is told to him.” The tweet received more than a thousand retweets, and his claim was also shared on Facebook by other users. And on the subreddit “r/conspiracy” -- a key vector for the Wayfair trafficking conspiracy theory -- a user posted a meme that had also been shared on Twitter and wrote that the theory claiming “Biden [is] using a hidden earpiece” was “legit.” Additionally, there had been at least a handful of videos about the conspiracy theory on TikTok.

The theory also circulated on far-right message boards. On one thread on 4chan’s “/pol/” message board, a user claiming “one of [their] friends is a member of the Biden campaign” wrote that Biden would have a “hidden earpiece” for the debate. The post received hundreds of responses. Other recent threads claimed Biden “waits for the words to be spoken into his earpiece” and is “undeniably wearing some sort of earpiece.”

And on TheDonald.win -- the site used by the now-banned subreddit “r/The_Donald” -- hundreds of users “upvoted” a post speculating that Biden “will wear an earpiece for tomorrow’s debate.” Other posts shared the same meme that had also spread on Reddit and Twitter and a screenshot of a message supposedly from far-right anti-Muslim bigot Laura Loomer on social media platform Parler saying, “I hope someone checks Joe Biden’s ears tomorrow for an ear piece.”

This is not the first conspiracy theory involving Biden’s ears during the 2020 presidential campaign to spread on these platforms: Last year, QAnon supporters spread a false claim that Biden’s earlobes were proof that he had somehow been cloned or replaced with a body double.