• by Wendy Davis , Staff Writer @wendyndavis, October 28, 2016

Two years ago, the White House warned in a report on Big Data that personalized ads carried the potential for discrimination that could harm consumers.

At the time, the concern seemed largely theoretical. But today, ProPublica reported that Facebook enables advertisers to prevent their ads from being shown to users who belong to certain "ethnic affinity" groups -- including people Facebook has identified as having an ethnic affinity of black, Asian-American and Hispanic. The company apparently doesn't have an ethnic affinity category for white users.

It's illegal to publish housing or job ads that discriminate based on factors including race, religion, sex and national origin.

Nonetheless, ProPublica reportedly was able to use Facebook's self-service tool to create an ad for an event aimed at renters, and then block it from pages of users who Facebook classified as having an ethnic affinity of black, Asian-American or Hispanic. The ad reportedly was approved by Facebook 15 minutes after ProPublica arranged to purchase it.

Facebook hasn't yet responded to MediaPost's questions. But a company representative told ProPublica that Facebook enables marketers to target ads by ethnic affinity for legitimate purposes, including testing. He added that an advertiser may want to send Spanish-language ads to people classified as having a Hispanic affinity.

He also reportedly said that the company's policies prohibit advertisers from using targeting capabilities to discriminate, and requires advertisers to comply with the law.

Facebook's procedure for assigning users to an ethnic affinity group appears murky at best. A company spokesperson reportedly told ProPublica that the social networking service "assigns members an ‘Ethnic Affinity’ based on pages and posts they have liked or engaged with on Facebook.”

The spokesperson also says that "ethnic affinity" isn't the same as race -- although, as ProPublica pointed out, Facebook included the option in a category of its tool devoted to demographics.

Facebook's ethnic affinity targeting isn't new. Earlier this year, the company drew attention for a campaign that marketed "Straight Outta Compton" by race.

But today appears to mark the first time that questions have been raised about whether the targeting enables discriminatory job or housing ads.

The answer to those questions isn't yet clear. But if it turns out that landlords, real estate agents or employers have used Facebook's targeting options to discriminate, the company could find itself facing new legal pressures.

In 2008 a federal appellate court ruled that Roommates.com may be liable for helping to match roommates based on race, and other unlawful criteria. The Web site argued in that case that the federal Communications Decency Act immunized it from discrimination lawsuits based on content created by users, but the 9th Circuit Court of Appeals rejected the roommate-matching site's argument.