Angela Lang/CNET

Facebook told Joe Biden's presidential campaign that it wasn't going to remove an ad by Donald Trump's reelection campaign despite claims it contains misinformation about the former vice president, a move that's drawing scrutiny from some Democratic lawmakers.

Last week, Trump's campaign ran a 30-second video on Facebook that stated Biden had promised Ukraine $1 billion if officials in that country fired the prosecutor investigating a company affiliated with Biden's son. There's no evidence to support the claim, which has been debunked by fact-checking groups and media reports.

The incident underscores Facebook's difficulty in crafting policies that prevent the spread of misinformation, a concern ahead of the 2020 elections. The company's policies draw a distinction between statements made by politicians and links to third-party information. The social network allows politicians to make statements, even false ones, but will limit the spread of links to false information made by third parties. The nuance can be lost on many observers, including the Biden campaign.

"The spread of objectively false information to influence public opinion poisons the public discourse and chips away at our democracy," TJ Ducklo, a Biden spokesman, said in a statement. "It is unacceptable for any social media company to knowingly allow deliberately misleading material to corrupt its platform."

In a letter to the Biden campaign on Monday, Facebook said it stands by its hands-off approach to political speech. The social network reiterated that it doesn't send ads and other posts from politicians to fact-checkers.

"Our approach is grounded in Facebook's fundamental belief in free expression, respect for the democratic process, and the belief that, in mature democracies with a free press, political speech is already arguably the most scrutinized speech there is," wrote Katie Harbath, Facebook's public policy director for global elections. "Thus, when a politician speaks or makes an ad, we do not send it to third party fact checkers."

The letter, which was obtained by CNET, says that if a politician shares content, such as links to an article or videos that have been debunked by fact checkers, Facebook will show it lower in people's News Feeds and reject the inclusion of that content in ads. The company said there's a difference though when a politician makes a false claim or statement.

"If the claim is made directly by a politician on their Page, in an ad or on their website, it is considered direct speech and ineligible for our third-party fact checking program," Harbath wrote.

The ad also appeared on Twitter and YouTube but both companies said it didn't violated its policies, according to The New York Times. CNN reported that it refused to air the Trump ad.

Last month, Facebook said it exempts politicians from its third-party fact-checking process, a policy it said has been in place for more than a year. Nick Clegg, Facebook's VP of Global Affairs and Communications, said at the Atlantic Festival in Washington DC that it wasn't the social network's role to "intervene when politicians speak." There are exceptions such as when speech endangers people's lives.

Biden's campaign manager Greg Schultz argued in a Oct. 4 letter to the social network that the Trump ad goes against the company's pledge to combat misinformation. "That pledge is implicated by this ad, and we expect Facebook to follow it," Schultz said in a letter obtained by CNET.

Tim Murtaugh, a spokesman for Trump's campaign, said in a statement that the ads were accurate. But Factcheck.org notes that while Biden threatened to withhold US money from Ukraine, there is no evidence that he did this to help his son, which is what the Facebook ad implies. The ad from the Trump campaign also states, "Democrats are trying to use Joe Biden's Ukraine scandal to steal the 2020 election by IMPEACHING the President."

Facebook's approach to political speech has received pushback from other politicians.

In a tweet, presidential candidate Elizabeth Warren, a US Democratic senator from Massachusetts, said that Facebook was "deliberately allowing a candidate to intentionally lie to the American people."

"This is a serious threat to our democracy. We need transparency and accountability from Facebook," she tweeted.

Facebook already helped elect Donald Trump once. Now, they're deliberately allowing a candidate to intentionally lie to the American people.



This is a serious threat to our democracy. We need transparency and accountability from Facebook. https://t.co/anu0pWSqS5 — Elizabeth Warren (@ewarren) October 9, 2019

Facebook has taken down ads from the Trump campaign for violating its advertising policies. In November 2018, the social network removed a controversial immigration ad by Trump's reelection campaign for violating its rules against "sensational content."

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Originally published Oct. 9, 8:25 a.m. PT.

Update, 3:43 p.m. PT: Adds more background.

Update, 4:16 p.m. PT: Adds Biden's campaign manager remarks.