schwit1 quotes a report from ProPublica: Imagine if, during the Jim Crow era, a newspaper offered advertisers the option of placing ads only in copies that went to white readers. That's basically what Facebook is doing nowadays. The ubiquitous social network not only allows advertisers to target users by their interests or background, it also gives advertisers the ability to exclude specific groups it calls "Ethnic Affinities." Ads that exclude people based on race, gender and other sensitive factors are prohibited by federal law in housing and employment. You can view a screenshot of a housing advertisement that ProPublica's Julia Angwin and Terry Parris Jr. purchased from Facebook's self-service advertising portal here. The report adds: "The ad we purchased was targeted to Facebook members who were house hunting and excluded anyone with an "affinity" for African-American, Asian-American or Hispanic people. (Here's the ad itself.) The Fair Housing Act of 1968 makes it illegal "to make, print, or publish, or cause to be made, printed, or published any notice, statement, or advertisement, with respect to the sale or rental of a dwelling that indicates any preference, limitation, or discrimination based on race, color, religion, sex, handicap, familial status, or national origin." Violators can face tens of thousands of dollars in fines. The Civil Rights Act of 1964 also prohibits the "printing or publication of notices or advertisements indicating prohibited preference, limitation, specification or discrimination" in employment recruitment. Facebook's business model is based on allowing advertisers to target specific groups -- or, apparently to exclude specific groups -- using huge reams of personal data the company has collected about its users. Facebook's micro-targeting is particularly helpful for advertisers looking to reach niche audiences, such as swing-state voters concerned about climate change. Facebook says its policies prohibit advertisers from using the targeting options for discrimination, harassment, disparagement or predatory advertising practices.