The Taft Court unanimously invalidated a Texas law that prohibited blacks from voting in party primary elections in Nixon v. Herndon (1927). The statute provided that “in no event shall a negro be eligible to participate in a Democratic party primary election held in the State of Texas.” L. A. Nixon, an African American living in El Paso, contended that the statute violated his constitutional rights under the Fourteenth and Fifteenth Amendments. Justice Oliver Wendell Holmes wrote the Court’s opinion, finding a clear violation of the Fourteenth Amendment Equal Protection Clause. He wrote that it “seems to us hard to imagine a more direct and obvious infringement of the Fourteenth [Amendment].” Holmes noted that the amendment had been passed “with a special intent to protect the blacks from discrimination against them.”

Texas did not become a bastion of equality for black voters after the decision. The state then allowed the Democratic Party’s executive committee to determine voter qualifications, which they did by race. Although the Hughes Court invalidated that practice in Nixon v. Condon (1932), the state still did not stop its racial discrimination. The Stone Court finally ruled in Smith v. Allwright (1944) that white-only primaries were unconstitutional whether initiated by state or party officials.