The Supreme Court has agreed to decide whether Arizona may require documentary proof of citizenship when a person registers using the state’s own registration form, and whether Arizona may cancel registrations in the 90 days before a federal election under a programme aimed at suspected noncitizens. The case is Republican National Committee v. Mi Familia Vota, No. 25-1017. The Court granted review on 29 June 2026, according to the Arizona State Law Journal’s account of the docket, and the docket records that argument was set for Tuesday, 8 December 2026. No decision has been issued.

Noncitizens may not vote; that qualification is not in dispute. The dispute is narrower. It is about evidence — what proof an applicant must supply, on which form, and whether the state or Congress controls that procedure for federal elections.

The question before the Court

Arizona has two registration forms. One is the federal form, created under the National Voter Registration Act of 1993 (NVRA) and maintained by the U.S. Election Assistance Commission. It asks an applicant to attest, under penalty of perjury, that they are a United States citizen. It does not require a birth certificate, passport or other attached document. The other is Arizona’s own state form. Arizona law, as amended in 2022, requires documentary proof of citizenship for state-form applicants and directs officials to reject a state-form application without satisfactory evidence.

The U.S. Court of Appeals for the Ninth Circuit held that key parts of the 2022 laws violated the NVRA. The Supreme Court must decide whether that reading was correct, and whether a 2018 consent decree — a court-approved agreement in earlier litigation — also bars enforcement of the newer requirement for state-form applicants seeking federal registration.

A second question concerns list maintenance. The 2022 laws require regular roll checks against available databases, notice to a person identified as a suspected noncitizen, and cancellation if satisfactory evidence is not supplied within 35 days. The NVRA restricts systematic removal programmes in the 90 days before a federal election. The Court must decide whether that restriction reaches Arizona’s programme. The parties disagree sharply, and the difference between a general purge and a targeted removal of people said never to have qualified is central.

Two forms, two ballots: the federal-only voter

The result is a category called “federal-only” voters. A person who attests to citizenship but supplies no documentary proof — and whose citizenship cannot otherwise be verified through state records — may vote in federal elections only, not in state and local elections, unless proof is later supplied. The Arizona State Law Journal stresses that a federal-only registrant is not necessarily a noncitizen. What is missing is documentary confirmation sufficient for full-ballot status. Only citizens are legally eligible to register, and federal-only registrants must still attest to citizenship.

As of 2 January 2026, Arizona reported 44,627 federal-only registrants, according to the Journal, citing Arizona Secretary of State data. That total also includes voters lacking documented proof of residency, not citizenship alone, so it is not a count of people whose citizenship alone is undocumented. It does show that the form used, and the documents officials hold, can produce different ballot rights at the same address.

Arizona officials recognise documents including certain driver’s licences, passports, birth certificates, naturalisation documents and specified tribal records, according to the Journal’s summary of Secretary of State guidance. The National Conference of State Legislatures sets out the older Arizona statute in similar terms. The current list should be checked in the official sources linked at the end of this article; this explainer gives no personal advice.

Proposition 200 and the 2013 decision

Arizona voters adopted Proposition 200 in 2004, requiring documentary proof of citizenship for registration. In Arizona v. Inter Tribal Council of Arizona, Inc. (2013), the Supreme Court held by 7–2 that the NVRA pre-empted Arizona’s attempt to require documentary proof from applicants using the federal form. The NVRA requires states to “accept and use” the federal mail form for federal elections, and that form requires only an attestation under penalty of perjury. Arizona could not demand more from a federal-form applicant as a condition of federal registration.

The 2013 decision did not hold that proof of citizenship is unconstitutional in general, and it did not decide what Arizona could require on its own form. Justice Antonin Scalia’s majority opinion distinguished two powers: states prescribe voter qualifications, subject to constitutional limits, while Congress may “make or alter” regulations governing the manner of congressional elections under the Elections Clause. Registration procedures fall within that manner authority, the Court held, and are therefore subject to congressional regulation. The new case asks the Court to draw that line again, this time for the state form.

After 2013, Arizona ran a two-track system: federal-form applicants without documentary proof could vote in federal elections only. In 2018, the Secretary of State and the Maricopa County Recorder entered a consent decree under which recorders would accept state-form applications without documentary proof, register otherwise qualified applicants for federal elections, and check motor-vehicle records, leaving an applicant federal-only unless proof was supplied. Whether that agreement still binds Arizona after the 2022 laws is now before the Court.

The 2022 laws: H.B. 2492 and H.B. 2243

H.B. 2492 requires, except for the federal form, that an application be accompanied by satisfactory evidence of citizenship, and directs officials to reject a state-form application lacking it while sending notice. It also restricted federal-only voters, including limits on presidential-election and mail voting that challengers contested. H.B. 2243 requires regular database checks, notice, and cancellation within the 35-day process described above.

Challengers — including Mi Familia Vota, Voto Latino, the League of United Latin American Citizens and other groups — argued that the laws denied eligible voters the right to vote based on which form they used and whether they could obtain paperwork. Voters already attest to citizenship and residence under penalty of perjury, they argued, and federal law bars additional requirements for federal registration. Arizona and its supporters argued that requiring proof of an existing qualification is part of the state’s authority to determine eligibility, and that the NVRA does not bar a state from setting terms for its own form.

The Ninth Circuit held in February 2025 that key provisions violated the NVRA and that the 2018 consent decree remained binding for state-form applicants seeking federal registration, as summarised in the Journal. It also addressed proof-of-residence, checkbox and birthplace provisions. The Supreme Court questions turn principally on the state-form proof requirement, the consent decree, and the 90-day programme.

The arguments on each side

The petitioners — the Republican National Committee, Arizona legislative leaders and the State of Arizona in part — argue that the Ninth Circuit read the NVRA too broadly. The Act guarantees that the federal form suffices for federal registration, they argue; it does not follow that every rule for a state-created form is governed by the same limit. A state that creates its own form retains authority to require documentary proof from applicants who choose it, in their account. The United States filed a brief supporting the petitioner in part, according to the docket, which lists a brief of the respondent United States in support filed on 28 August 2026.

The respondents — Mi Familia Vota and allied groups, the Democratic National Committee and the Arizona Democratic Party, and other voting-rights organisations — argue that Congress has prescribed the requirements for federal registration and Arizona cannot add documentary requirements for state-form applicants beyond those the NVRA permits. A state form used for federal registration must require only information necessary to assess eligibility, they argue, and the consent decree independently bars the challenged enforcement. The docket records extensive amicus briefing on both sides in September and October 2026, from election officials, former members of Congress, civil-rights organisations and state officials.

Both sides also dispute practical effects. Supporters call documentary proof a routine integrity measure. Challengers argue it burdens eligible citizens who cannot readily produce a birth certificate or passport — including older voters, rural residents and some naturalised citizens — and that database checks can wrongly flag naturalised citizens. This article does not resolve those disputes.

What a ruling would change — and what it would not

If the Court rules for Arizona, the direct effect would be that Arizona could enforce documentary proof for state-form applicants and continue its 90-day list-maintenance programme, subject to the opinion’s precise terms and any claims it does not decide. The federal form would remain available: Inter Tribal Council requires it to be accepted for federal elections, and nothing summarised here asks the Court to overrule that holding for the federal form itself. A ruling for Arizona would likely encourage other states to adopt similar state-form requirements, but it would not by itself impose a national documentary-proof requirement or change the federal form.

If the Court rules for the respondents, the state-form requirement and the challenged 90-day programme would remain barred as the Ninth Circuit held, subject to the Court’s reasoning. Arizona could still verify citizenship through available data sources, as the NCSL notes states commonly do, and could ask the Election Assistance Commission to add a documentary-proof instruction to the federal form through the process identified in 2013. Such a ruling would not decide that citizenship may not be required to vote, and it would not authorise noncitizens to vote. It would decide that Congress’s procedure controls over the additional state requirement at issue.

Either way, the ruling would not change eligibility for the 3 November 2026 midterm elections: argument is set for 8 December, five weeks later. For readers following the 2026 midterm elections and what is on the ballot, the point is timing — this case concerns future registrations. Election administration varies by state, as Texas Senate race coverage illustrates for another state’s federal contest. Congress could also amend the NVRA, but most legislation needs 60 votes to end Senate debate, the rule explained in our article on what a filibuster is and how the 60-vote rule works. No prediction is made here about Congress or the Court.

What happens next

After argument, the Court will issue a written opinion stating the holding, reasoning and limits. This explainer will be updated on the same URL after argument and after the decision.

For personal registration questions, use official sources only. Vote.gov links to state registration information, and the Arizona Secretary of State publishes Arizona’s requirements and accepted proof. This article does not provide personal voting advice. Check current official guidance before submitting a form, because court orders and guidance can change while a case is pending.

Frequently asked questions

Can Arizona require proof of citizenship to register to vote?
That is the question for state-form applicants. In 2013 the Court held Arizona could not require documentary proof from federal-form applicants. Whether the state form is different is the central issue in RNC v. Mi Familia Vota.

What is the difference between the federal form and the state form?
The federal form requires an attestation of citizenship under penalty of perjury, with no attached document. The 2022 Arizona law requires documentary proof with the state form. The case turns on whether federal law limits what the state form may require for federal registration.

What is a federal-only voter?
A registrant who attests to citizenship but lacks documentary confirmation sufficient for full-ballot status may vote in federal elections only in Arizona. The status reflects missing documentation, not a finding that the person is not a citizen.

When will the Supreme Court decide the case?
Argument is set for 8 December 2026, according to the docket. No decision date has been announced, and this article does not predict one. It will be updated when the decision is issued.

Updated: 28 October 2026. The case is pending. Argument is scheduled for 8 December 2026; no ruling has been issued. For official registration information, see Vote.gov and the Arizona Secretary of State.

Sources

• Supreme Court of the United States, “Docket for 25-1017 — Republican National Committee v. Mi Familia Vota” — https://www.supremecourt.gov/docket/docketfiles/html/public/25-1017.html
• Arizona State Law Journal, Iuri Macedo Piovezan, “One Voter, Two Electorates: Arizona’s Proof-of-Citizenship Law and the Federalism Problem in Voter Registration”, 5 October 2026 — https://arizonastatelawjournal.org/2026/10/05/one-voter-two-electorates-arizonas-proof-of-citizenship-law-and-the-federalism-problem-in-voter-registration/
• National Conference of State Legislatures, “Requiring Documentary Proof of Citizenship” — https://www.ncsl.org/elections-and-campaigns/requiring-documentary-proof-of-citizenship
• Official registration information: Vote.gov ; Arizona Secretary of State — https://azsos.gov/