Lucas v. Forty-Fourth General Assembly of Colorado (1963)

Lucas v. Forty-Fourth General Assembly of Colorado, 377 U.S. 713 (1964)

Case Summary

Andres Lucas, representing voters of urban Denver, challenged Colorado apportionment system on the basis that the Senate apportionment was not based on population, but a range of considerations that included population, natural boundaries and historical divisions.  Under his system, a one third minority of the population could successfully elect a majority to the Senate. Lucas raised Equal Protection Clause arguments relating to the dilution of his vote, similar to those raised in Reynolds v. Sims. Unique to this case, however, was the fact that though Colorado’s apportionment system was similar to those in other States, it had been approved by a majority vote of the electorate. The District Court ruled that in light of this fact, the plan satisfied the Fourteenth Amendment.  The case reached the Supreme Court on appeal.


The Supreme Court reversed the judgment of the District Court, ruling that the fact that an apportionment system was approved by the popular vote does not allow it to deny any voters equal representation in both houses, per the Reynolds ruling.  Though the Court reiterated its position that State elections permit some slight degree of flexibility in drawing districts in order to protect certain groups, these deviations from purely population based apportionment cannot be significant. A majority vote of the people could not, in the Court’s judgment, justify the dilution of even one person’s vote.

Impact on Redistricting

Lucas made it clear that, however popular, geographically based apportionment systems in State legislatures could not be enacted (short of a Federal Constitutional Amendment). The Reynolds decision was reinforced and its application broadened to include plans that the public had approved.