Explicitly racial zoning was struck down in Buchanan v. Warley (1917). Cities turned to rules that sounded neutral. In Village of Euclid v. Ambler Realty (1926), the Supreme Court upheld zoning that separated single-family homes from apartments, and single-family-only zoning spread across American suburbs. Because Black families had lower incomes and less wealth, often due to discrimination, rules that blocked cheaper housing kept many of them out.
Courts and lawmakers have pushed back. In the Mount Laurel decisions starting in 1975, New Jersey's Supreme Court required towns to allow their fair share of affordable housing. In 2018, Minneapolis approved a plan to allow up to three homes on lots once reserved for single-family houses, and Oregon passed a similar statewide law in 2019.
Exclusionary zoning matters because it decides who can live near good schools, jobs and parks. It also shapes school funding, since many districts rely on local property taxes, so housing barriers become education barriers too.