The campaign said the claim in the ad "has been demonstrated to be completely false." Politifact and Factcheck.org, organizations that Facebook works with for fact checking, debunked the 30-second ad soon after President Trump's camp distributed it.
In a recent update to its advertising policy on misinformation, Facebook wrote that it "prohibits ads that include claims debunked by third-party fact checkers or, in certain circumstances, claims debunked by organizations with particular expertise."
However, in the letter, Facebook's public policy director for global elections Katie Harbath underscored the company's policy to take a hands-off approach to posts from politicians. "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," Harbath wrote. "Thus, when a politician speaks or makes an ad, we do not send it to third-party fact checkers."
If a politician shares "a viral hoax -- like a link to an article or video that has previously been debunked, we will demote that content, display related information from fact checkers, and reject its inclusion in advertisements," Harbath noted. "That is different from a politician's own claim or statement — even if the substance of that claim has been debunked elsewhere. 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."
The Biden campaign said Facebook's response was "unacceptable." A spokesman said in a statement to CNN that the dissemination of "objectively false information to influence public opinion poisons the public discourse and chips away at our democracy."
Notably, the ad at the heart of the issue has also been distributed on YouTube and Twitter, both of which told the NYT it complied with their policies. However, CNN refused to air it, stating it "makes assertions that have been proven demonstrably false by various news outlets."
Senator Elizabeth Warren, one of Biden's rivals for the Democratic presidential nomination, is among those who have urged Facebook to take down the ad. Some lawmakers, including fellow presidential candidate Sen. Amy Klobuchar, have called for an overhaul of political ad rules to cover a broader swathe of advertising platforms beyond the likes of TV and radio.