John Howard Ferguson was an American lawyer and judge from Louisiana, most famous as the defendant in the Plessy v. Ferguson case.

Plessy v. Ferguson, 163 U.S. 537 (1896), was a landmark U.S. Supreme Court decision ruling that racial segregation laws did not violate the U.S. Constitution as long as the facilities for each race were equal in quality, a doctrine that came to be known as "separate but equal". The decision legitimized the many state laws re-establishing racial segregation that had been passed in the American South after the end of the Reconstruction era in 1877. Such legally enforced segregation in the south lasted into the 1960s.