In 1964, the U. S. Supreme Court ruled in Wesberry v. Sanders that members of the U.S. House of Representatives must be chosen from districts approximately equal in population. That same year, in Reynolds v. Sims, the Court ruled that members of both houses of a state legislature must be chosen from districts approximately equal in population.
In 1970, as required by the Texas Constitution after each national census, the Texas Legislature drew up a reapportionment plan for the Texas House of Representatives but was unable to agree upon a reapportionment plan for the Texas Senate. Litigation was immediately filed in a Texas District Court challenging the constitutionality of the reapportionment plan for the Texas House. The Texas Supreme Court eventually ruled that the legislature’s House reapportionment plan violated the Texas Constitution. Meanwhile, as required by the Texas Constitution, the Legislative Redistricting Board began the task of reapportioning the Texas Senate. Because of the judicial invalidation of the House reapportionment plan, the Board soon also had to work on reapportioning the Texas House.
In October 1971, the Board released its proposed reapportionment plans for both chambers of the Texas Legislature. Four lawsuits, eventually consolidated, were filed in a three-judge U.S. District Court. With respect to the House plan, these lawsuits alleged that the districts as drawn contained impermissible deviations from population equality and that the plan’s multi-member districts for Dallas and Bexar counties were constitutionally invalid because they diluted the voting strength of racial and ethnic minorities. The three-judge District Court upheld the reapportionment plan for the Senate but agreed with both arguments made by the plaintiffs and found the House plan unconstitutional. This court gave the Texas Legislature until July 1973 to reapportion the Texas House but did allow the Legislative Redistricting Board’s plan to be used for the 1972 elections except for the requirement that the multi-member districts for Dallas and Bexar counties be reconstituted into single-member districts. As provided by law, the judgment of the three-judge U.S. District Court was appealed directly to the U.S. Supreme Court.