Madeleine Varner

In February, Facebook said it would step up enforcement of its prohibition against discrimination in advertising for housing, employment or credit. But our tests showed a significant lapse in the company’s monitoring of the rental market. Last week, ProPublica bought dozens of rental housing ads on Facebook, but asked that they not be shown to certain categories of users, such as African Americans, mothers of high school kids, people interested in wheelchair ramps, Jews, expats from Argentina and Spanish speakers.