In 1959, several residents dissatisfied with Tennessee's legislative districts brought suit against the state in "Baker v. Carr". Like many other states, Tennessee had state legislative districts of unequal populations, and the plaintiffs sought more equitable legislative districts. In "Colegrove v. Green" (1946), the Supreme Court had declined to become involved in legislative apportionment and instead left the issue as a matter for Congress and the states. In "Gomillion v. Lightfoot" (1960), the Court struck down a redistricting plan designed to disenfranchise African-American voters, but many of the justices were reluctant to involve themselves further in redistricting. Frankfurter insisted that the Court should avoid the "political thicket" of apportionment and warned that the Court would never be able to find a clear formula to guide lower courts. Warren helped convince Associate Justice Potter Stewart to join Brennan's majority decision in "Baker v. Carr", which held that redistricting was not a political question and so federal courts had jurisdiction over the issue. The opinion did not directly require Tennessee to implement redistricting but instead left it to a federal district court to determine whether Tennessee's districts violated the Constitution. In another case, "Gray v. Sanders", the Court struck down Georgia's County Unit System, which granted disproportional power to rural counties in party primaries. In a third case, "Wesberry v. Sanders", the Court required states to draw congressional districts of equal population.