Along with Baker v. Carr (1962) and Reynolds v. Sims (1964), it was part of a series of Warren Court cases that applied the principle of "one person, one vote" to U.S. legislative bodies.

The decision had a major impact on representation in the House, as many states had districts of unequal population, often to the detriment of urban voters.

No right is more precious in a free country than that of having a voice in the election of those who make the laws under which, as good citizens, we must live.

Writing for the Court majority in Wesberry, Justice Black argued that a reading of the debates of the Constitutional Convention demonstrated conclusively that the Framers had meant, in using the phrase “by the People,” to guarantee equality of representation in the election of Members of the House of Representatives.

Justice Harlan further argued that the Convention debates were clear to the effect that Article I, § 4, had vested exclusive control over state districting practices in Congress and that the Court action overrode a congressional decision not to require equally populated districts.