Thornburg v. Gingles Establishes VRA Section 2 Three-Part Test

The Supreme Court unanimously upheld a lower court ruling striking down North Carolina's 1982 multimember legislative districts as diluting Black voting power under Section 2 of the Voting Rights Act. Justice Brennan wrote the majority opinion establishing three preconditions — now called the Gingles factors — that minority plaintiffs must satisfy before a court can find vote dilution. The ruling gave civil rights plaintiffs a workable framework to challenge redistricting plans that crack or pack minority communities.