The social network says hate speech accounts for a tiny fraction of the posts people see. It's relying on automated systems to catch it, but is under pressure to do better.
The Senate Judiciary Committee grilled Facebook's Mark Zuckerberg and Twitter's Jack Dorsey over how they handle false and misleading claims about the election, including from President Donald Trump.
Backed by Rebekah Mercer, Parler is now one of the most downloaded smartphone apps, as conservatives complaining of censorship by Facebook and Twitter seek out other social media alternatives.
Facebook, Twitter, YouTube and TikTok have stepped up efforts to curb the spread of misinformation about the election, but researchers say falsehoods thrive nearly unchecked on live videos.
The social network's crackdown comes after the former White House strategist was permanently suspended from Twitter. Facebook said the pages were using "deceptive tactics" to mislead people.
The group had amassed more than 360,000 members who shared false claims about voter fraud before the social network shut it down, citing "worrying calls for violence" from some members.
The chief executives of Facebook, Twitter and Google face skepticism from a Senate committee over their decisions about what content to allow and what to take down from their platforms.
Facebook's Mark Zuckerberg, Twitter's Jack Dorsey and Google's Sundar Pichai go before the Senate Commerce Committee to defend Section 230, a law that protects them from lawsuits over users' posts.
The Justice Department's lawsuit against Google is the clearest sign yet of the "Techlash" that has politicians on both sides of the aisle bristling at the power of Silicon Valley.
While Republicans accuse Facebook and Twitter of censoring free speech, one expert says the platforms should do more because U.S. voters are "more vulnerable to online disinformation" than ever.
The social media companies said they wanted to slow the spread of possibly false information. But their actions drew charges of censorship from President Trump and his allies.
The move is a reversal of Facebook's longstanding reluctance to block problematic content. Critics say public health misinformation has flourished on the social network.
Facebook's goal is to help messages about the safety and efficacy of vaccines reach a broad group of people, while prohibiting ads with misinformation that could harm public health efforts.
CEO Mark Zuckerberg, who previously considered such claims free speech, said his thinking has "evolved." Survivors had lobbied the social network to remove posts that deny the Holocaust.
