Facebook has long allowed advertisers to target users based on race—and exclude users based on race, too.
On Wednesday, Facebook said they're temporarily stopping that ability to exclude after repeated investigations uncovered how easy it is to discriminate.
The update comes after a ProPublica investigation published last week revealed advertisers can still target housing ads to white people only. That's damning not only because it violates the federal Fair Housing Act but also because ProPublica already made Facebook aware of the issue back in October 2016. Facebook later promised to step up its enforcement.
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The solution: algorithms.
The problem: algorithms didn't work perfectly.
Facebook said in February it would "build tools to detect and automatically disable the use of ethnic affinity marketing for certain types of ads."
It's important to note that Facebook's ad system doesn't explicitly allow for brands to target or to exclude people based on their race. Facebook doesn't require users to report their race. Instead, Facebook has a system called "ethnic affinity marketing" that creates subgroups of users for what race or cultural group Facebook thinks they are based on their behavior on and off the platform.
Clearly, the tools Facebook introduced earlier this year to prevent discrimination via these ads are not perfect. ProPublica's investigation from last week showed that they could buy a rental housing ad that excluded users based on race or ethnicity in a matter of minutes.
To give Facebook credit, the tools — or as Facebook likes to call them, "safeguards" — did protect against some abuse.
"Our safeguards, including additional human reviewers and machine learning systems have successfully flagged millions of ads and their effectiveness has improved over time," Ami Vora, vice president of product management at Facebook, said in a statement last week.
"Tens of thousands of advertisers have confirmed compliance with our tighter restrictions, including that they follow all applicable laws," she continued.
But ProPublica was able to demonstrate a flaw in the system, what Vora described as a "technical failure."
"Our systems continue to improve but we can do better," Vora wrote.
Before Facebook can determine how to do better, it has pulled the plug on the ability to exclude races in ad campaigns. That functionality will be removed for all advertisers as of Friday.
It's also conducted an audit of the exclusion tool that extends beyond racial and ethnic affinity groups. For example, Facebook will be analyzing how the tool can discriminate against the LGBTQ community and religious groups.
“Until we can better ensure that our tools will not be used inappropriately, we are disabling the option that permits advertisers to exclude multicultural affinity segments from the audience for their ads,” Facebook's Chief Operating Officer Sheryl Sandberg wrote in a letter to the Congressional Black Caucus dated Wednesday.
Lawmakers of the Caucus had reached out to Facebook last year about the issue and continued in conversations about the issue. One lawmaker said he is pleased by Facebook's decision to temporarily stop the exclusion functionality.
"Facebook's decision to disable its multicultural affinity advertising function is an appropriate action until the serious concerns associated with that feature are remedied. Thankfully, we've been able to establish a constructive pipeline of communication that's resulted in a positive step forward," Rep. Robin Kelly, a member of the Congressional Black Caucus and ranking member of the IT subcommittee, said in a statement on Wednesday.