The Materiality Provision of the Civil Rights Act of 1964 prohibits states from denying the right to vote over paperwork errors or omissions that are immaterial to a voter’s qualifications to vote. In Arizona, U.S. citizens may register to vote, regardless of where they were born. Notwithstanding that fact, in 2022, Arizona passed legislation mandating that prospective voters include their birthplace on voter registration forms. If a voter does not include her birthplace on a form, then she will not be registered to vote.

Several challengers filed suit. After a ten-day trial, the United States District Court for the District of Arizona held that the requirement violates the Materiality Provision because “an individual’s birthplace is not material to determining her eligibility to vote.” On appeal in the Ninth Circuit, the State of Arizona argues that the district court did not give sufficient “weight” to the state’s justifications for the requirement. Separately, the Republican National Committee, Warren Petersen, and Ben Toma (“RNC and Legislative Appellants”) argue that a state can make the Materiality Provision inapplicable to certain information requested from voters simply by making that information necessary to register to vote.

In August 2024, CAC filed an amicus brief in support of the challenges to the birthplace requirement. The appellants’ arguments trying to limit the Materiality Provision’s scope are not only at odds with the Provision’s text and history, they would also undermine Congress’s ability to help realize the Constitution’s promise of voting equality. Our brief makes three principal points.

First, the Fifteenth Amendment gives Congress sweeping power to enforce the Amendment’s ban on racial discrimination in voting. The Fifteenth Amendment provides that “[t]he right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude.” To make the Fifteenth Amendment’s guarantee a reality, the Framers explicitly provided that “Congress shall have power to enforce this article by appropriate legislation.” Its authors explained that this Enforcement Clause gives Congress a broad “affirmative power” to secure the right to vote.

Second, Congress used its Fifteenth Amendment enforcement power to enact the Civil Rights Act of 1964 and prohibit arbitrary denials of the right to vote. Despite the Fifteenth Amendment’s broad prohibition of racial discrimination in voting, states devised novel procedures to prevent Black citizens from voting. Congress sought to strengthen federal civil rights protections with the Civil Rights Act of 1964, and its authors were specifically concerned with arbitrary practices that disenfranchised voters with “irrelevantly strict” requirements.

Third, the birthplace requirement violates the Materiality Provision. Because the statute does not define “material,” the term should be given its ordinary meaning: “highly important,” or “of much consequence.” Here, birthplace is immaterial to a voter’s qualifications. Arizona argues that courts should “give weight” to state’s justifications for voter registration requirements when assessing materiality. This is wrong. Given that the Materiality Provision was adopted to address concerns about state abuses, it would make no sense to defer to state judgments about whether omissions or errors in paperwork are material. Similarly, RNC and Legislative Appellants’ argument that the Materiality Provision does not apply if a state decides to make certain information required on registration forms is irreconcilable with the text and history of the Materiality Provision.

The Ninth Circuit should affirm the district court’s permanent injunction against the birthplace requirement and reject Arizona’s unlawful attempt to disenfranchise voters.