Baseless conspiracy theories about certain voter fraud in November are widely viewed on TikTok, which globally has more than a billion active users each month. Users cannot search the #StopTheSteal hashtag, but #StopTheSteallll had accumulated nearly a million views until TikTok disabled the hashtag after being contacted by The New York Times. Some videos urged viewers to vote in November while citing debunked rumors raised during the congressional hearings into the Jan. 6, 2021, attack on the Capitol. TikTok posts have garnered thousands of views by claiming, without evidence, that predictions of a surge in Covid-19 infections this fall are an attempt to discourage in-person voting.

The spread of misinformation has left TikTok struggling with many of the same knotty free speech and moderation issues that Facebook and Twitter have faced, and have addressed with mixed results, for several years.

But the challenge may be even more difficult for TikTok to address. Video and audio — the bulk of what is shared on the app — can be far more difficult to moderate than text, especially when they are posted with a tongue-in-cheek tone. TikTok, which is owned by the Chinese tech giant ByteDance, also faces many doubts in Washington about whether its business decisions about data and moderation are influenced by its roots in Beijing.

“When you have extremely short videos with extremely limited text content, you just don’t have the space and time for nuanced discussions about politics,” said Kaylee Fagan, a research fellow with the Technology and Social Change Project at the Harvard Kennedy School’s Shorenstein Center.