Further, according to ProPublica, the social network approved all but one of them within minutes, as their image above demonstrates. The other ad sought to exclude renters who were "interested in Islam, Sunni Islam and Shia Islam," which Facebook allowed after just 22 minutes. The platform's policies state that their vetting process should have flagged the discriminatory language in each of these advertisement requests, but that didn't happen.

Federal law prohibits ads from discriminating based on race in three areas -- housing, employment and credit. Not coincidentally, these were the areas that Facebook claimed it was ended its 'ethnic affinity' advertising options. The Department of Housing and Urban Development was previously investigating Facebook for its advertising policies, but confirmed to ProPublica that it had closed the inquiry.

When reached for comment, Facebook said a technical error miscategorized the ProPublica ads, so compliance and review alarms weren't triggered. Facebook provided this statement to Engadget from its VP of Product Management Ami Vora: