The U.S. Supreme Court ruled unanimously in Yick Wo v. Hopkins (1896) that San Francisco officials violated the equal-protection rights of Chinese laundry operators Yick Wo and Wo Lee by subjecting them to more onerous regulation than white laundry owners. The city passed a law that provided: “It shall be unlawful, from and after the passage of this order, for any person or persons to establish, maintain, or carry on a laundry, within the corporate limits of the city and county of San Francisco, without having first obtained the consent of the board of supervisors, except the same be located in a building constructed either of brick or stone.”

The evidence established that two hundred Chinese laundry owners, most of whom had wooden structures, were denied operating permits, while seventy-nine of eighty Caucasian laundry operators were granted permits. According to the Court, this overwhelming pattern of discrimination violated the Equal Protection Clause of the Fourteenth Amendment.

Writing for the Court, Justice Stanley Matthews concluded: “The fact of this discrimination is admitted. No reason for it is shown, and the conclusion cannot be resisted that no reason for it exists except hostility to the race and nationality to which the petitioners belong, and which, in the eye of the law, is not justified. The discrimination is therefore illegal, and the public administration which enforces it is a denial of the equal protection of the laws, and a violation of the Fourteenth Amendment of the Constitution.”

The case is important because it established that a law can violate the Equal Protection Clause even thought it is race-neutral on its face as long as proof can be established showing a discriminatory pattern of operation.