According to the federal Fair Housing Act, also known as Title VIII of the Civil Rights Act of 1968, advertisements published "with respect to the sale or rental of a dwelling that indicates any preference, limitation, or discriminate based on race, color, religion, sex, handicap, familial status, or national origin."
Facebook announced in February new algorithms would detect and reject ads based on race.
A ProPublica investigation found that it is possible to get around those systems on the platform. The non-profit bought housing ads and requested Facebook to exclude showing them to African Americans, mothers of high school kids, people interested in wheelchair ramps, Jews, expats from Argentina and Spanish speakers.
"Every single ads was approved within minutes," ProPublica reported Tuesday afternoon.
The only exception was an advertisement blocking out potential housing seekers "interested in Islam, Sunni Islam and Shia Islam," which Facebook approved in 22 minutes.
A Facebook executive said Tuesday the company was "disappointed that we fell short of our commitments."
"The rental housing ads purchased by ProPublica should have, but did not, trigger the extra review and certifications we put in place due to a technical failure," the Facebook representative said.
A September investigation by the non-profit news outlet found that Facebook let advertisers target an audience of people interested in topics including "jew haters," "how to burn jews" and "history of ‘why jews ruin the world.'"
"As a jew, as a mother and as a human being, I know the damage that can come from hate. The fact that hateful terms were even offered as options was totally inappropriate and a fail on our part," Sheryl Sandberg, Facebook COO, said in response to the investigation.