In recent months, the world's most powerful social network has tried to balance free political speech with fact-checking paid and organic posts.
Facebook policy says political ads can make false claims while non-political advertisers can't.
Business Insider was easily able to run Facebook ads with misinformation, though.
First, we set up a private business page called Americans Who Support Data Privacy. Over several days, we used Facebook Ads Manager to run ads that lied about the hot-button political topics of immigration and firearms. The ads were targeted to a tiny portion of Facebook users and we took down the ads after 24 to 48 hours.
We showed the ads to Facebook, which said it sends ads to third-party fact-checkers based on multiple signals, which may include getting feedback that an ad is false. Facebook said several of our ads shouldn't have run "because they are about politics or social issues and don't have the appropriate authorization and disclosures."
One ad repeated the false rumor that undocumented immigrants who participate in the 2020 census will be deported
One ad was targeted to Spanish-speaking Facebook users who had recently been near top ports of entry along the US-Mexico border.
The ad featured an image of two men in handcuffs and linked to the homepage of US Immmigration and Customs Enforcement. Its copy implied that authorities would use the 2020 census to arrest and deport undocumented immigrants.
Facebook approved the ad even though the Trump administration in fact abandoned attempts to include a citizenship question on the census in July after a string of court losses.
Another ad warned ICE and Customs agents that they "will face justice"
A second ad was narrowly targeted to employees of ICE and US Customs and Border Protection, a group that included only a few hundred Facebook users.
The ad falsely suggested that employees of the two federal agencies, which have been the subject of protests during Trump's presidency, could face "justice" or be charged with unspecified "war crimes."
This post linked back to the homepage of RAICES Texas, a non-profit that provides legal services to immigrant and refugee families.
A second, nearly identical and also false version of the same ad was not approved by Facebook. It was unclear why the earlier ad ran while the other was rejected. The only discernible difference between the two was in the copy, which in the second ad read "ICE, you could be charged with war crimes" and "Justice is coming for ICE!"
Facebook said in an email that the rejected ad did not comply with the company's advertising policies.
Per Facebook, the ad was placed in the "social issues, elections or politics" category, and a related link stated that any page running such an ad must complete the process to be authorized as a political group.
We also tried to run other misleading ads that failed to clear Facebook's filter, such as one targeting evangelical Christians that included an image of Democratic presidential candidate Beto O'Rourke and falsely suggested that if elected, he would force their churches to perform same-sex marriages.
The last ad targeted employees of the NRA and Smith & Wesson and said they could "face charges" under the next president
Our last ad targeted people who are firearms instructors or work for Smith & Wesson Inc. or the NRA Institute for Legislative Action, the gun rights group's lobbying arm.
The ad falsely told users that their respective employers "enable criminals" and that they may "face charges" under the next administration. The ad ran on Facebook and Instagram for about 24 hours.
In total, the three ads reached a miniscule portion of Facebook and Instagram's estimated 2.41 billion and 1 billion respective worldwide monthly active users. For example, the census ad received more than 3,600 impressions on Facebook while the ICE post got just over 500.
But users saw them and responded to them.
Facebook's scale makes misinformation impossible to solve
Ad fraud specialist Augustine Fou said Facebook's sheer scale makes it impossible to review every ad.
Facebook head Mark Zuckerberg has been emphasizing that responsibility for determining what is true and false ultimately lies with Facebook's users rather than the company itself.
David Carroll, associate professor of media design at Parsons and an ad-tech expert, said the problem with this strategy is that it lets everyday users promote misinformation — as illustrated by the ads Business Insider was able to run.
"[Facebook] is not only about connecting and communicating," he said. "Everybody can be an advertiser."