360 U.S. 45 (1959), argued 18–19 May 1959, decided 8 June 1959 by vote of 9 to 0; Douglas for the Court. Lassiter is an important case in the history of the federal protection of voting rights. The Court rejected a black citizen's challenge to a state literacy test, finding that states have broad powers to determine the conditions of suffrage. The literacy test applied to voters of all races, and the Court would not draw the inference that it was being used to facilitate racial discrimination.
Lassiter had to be addressed in assessing the constitutionality of the Voting Rights Act of 1965. The act temporarily suspended literacy and other tests imposed as prerequisites to voting. In South Carolina v. Katzenbach (1966), the Court distinguished Lassiter on the ground that in most states covered by the 1965 act prerequisites to voting were instituted and administered in a discriminatory fashion for many years. In Katzenbach v. Morgan (1966), New York tested the 1965 act's effective prohibition of application of an English literacy requirement to persons who completed the sixth grade in a non-English-speaking American school. The act thus gave voting privileges to many former residents of Puerto Rico who had migrated to New York.
If the Court had adhered to its approach in Lassiter it would have struck down the literacy requirement only if a court would conclude that the requirement discriminated against non-English-speakers. But the Court refused to ask the Lassiter-like question whether the judiciary would find the English literacy requirement unconstitutional. Section 5 of the Fourteenth Amendment required only that legislation be appropriate to enforce the Equal Protection Clause of the Fourteenth Amendment. It was Congress's decision to make. The challenged provision sought to secure for the New York Puerto Rican community nondiscriminatory treatment and was thus appropriate to enforce the Equal Protection Clause. Subsequent amendments to the Voting Rights Act prohibited all literacy tests as a prerequisite for voting.