Facebook is facing a lawsuit over its deployment of ethnic affinity ad targeting.

The class-action lawsuit, filed in California federal court last week, claims that this targeting violates federal fair housing and civil rights laws, by making it possible to hide ads for housing and recruitment ads from certain groups. It follows a ProPublica article published at the end of last month, which demonstrated how it was possible to exclude users from seeing ads based on their race or gender.

The lawsuit, first reported by Business Insider, alleges that these ads enable “discrimination based on race, color, religion, sex, familial status, and national origin” in a way that is illegal under the Fair Housing Act and Title VII of the 1964 Civil Rights Act.

The lawsuit includes a list of the kinds of groups Facebook enables advertisers to target – or, more importantly, exclude – including African-Americans, indigenous peoples, working women, widows, members of the Sunni or Shia Islam faith, and immigrants.

“No user can tell whether they are subject to illegal discrimination, because the discrimination occurs with the ads they do not see,” argues the lawsuit.

The intent of the lawsuit is not to remove Facebooks demographic targeting completely – it concedes that are some legal and desirable uses of the technology – but rather to stop it being used in ways that could hinder certain groups from finding homes or employment.

Facebooks position, as laid out in a blog post by head of multicultural Christian Martinez, is that this kind of usage is against its ad policies.

“Our ad policies strictly prohibit this kind of advertising, and it’s against the law,” said Martinez. “If we learn of advertising on our platform that involves this kind of discrimination, we will take aggressive enforcement action. We also realize that, as a website, we often aren’t in a position to know the details of an apartment rental or job application — and so we will also remove an ad from our platform if the government agency responsible for enforcing discrimination laws tells us that the ad reflects illegal discrimination.”