Thornburg v. Gingles

Facts of the Case

Black citizens of North Carolina who were registered to vote filed an action in the United States District Court for the Eastern District of North Carolina. They alleged in part that the state had diluted black voting strength in violation of 2 of the Voting Rights Act of 1965 (


Did the District Court err by holding that a North Carolina redistricting plan unlawfully discriminated against blacks in six voting districts?


No. The Court found that five of the six contested districts discriminated against blacks by diluting the power of their collective vote. Justice William J. Brennan Jr. delivered the opinion for a unanimous court. The District Court properly performed its function to ascertain whether minority group members constitute a politically cohesive unit and to determine whether whites vote sufficiently as a bloc usually to defeat the minority’s preferred candidate. The District Court correctly analyzed data from three election cycles in North Carolina to determine that the black voters strongly supported black candidates, whereas whites usually voted against black candidates. The redistricting plan apportioned politically cohesive groups of black voters into districts where blocs of white voters would consistently defeat the black candidates. In violation of the Voting Rights Act, this damaged the ability of black citizens to participate equally in the political process and to elect candidates of their choice.

Case Information

  • Citation: 478 US 30 (1986)
  • Argued: Dec 4, 1985
  • Decided Jun 30, 1986