Plessy v. Ferguson, argued on April 13, 1896, and decided on May 18, 1896, is probably best known for giving the United States the “separate but equal” doctrine. The case probably ranks close to Dred Scott v. Sandford (1857) as one of the most influential and thoroughly repudiated cases the Supreme Court has ever decided. The majority opinion was written by Justice Henry Billings Brown of Massachusetts, and it gained the assent of six additional justices. That opinion provided a legal imprimatur to segregation and the Jim Crow system of laws that flourished from the late nineteenth century through much of the twentieth century.