Arizona v. Inter Tribal Council of Ariz., Inc.
The Court ruled that Arizona cannot refuse to register voters who use the federal mail voter-registration form simply because they didn't attach extra documents proving citizenship, since federal law requires states to "accept and use" that standard form.
The decision leaves Arizona free to keep requiring proof of citizenship on its own state-created registration form and to ask a federal agency to add a citizenship-document requirement to the federal form, but it can't unilaterally add that requirement when a voter uses the federal form.
“We conclude that the fairest reading of the statute is that a state-imposed requirement of evidence of citizenship not required by the Federal Form is "inconsistent with" the NVRA's mandate that States "accept and use" the Federal Form.”
The Court's core holding that Arizona's added documentation requirement conflicts with federal law.
How it got here: A federal trial court rejected the challenge on summary judgment; the Ninth Circuit, sitting en banc, reversed and sided with the challengers; Arizona sought Supreme Court review.
The Case in Depth
What happened
Arizona voters passed Proposition 200, requiring county officials to reject any voter-registration application, including the federal government's standard mail-in form, unless it came with documents like a passport, birth certificate, or tribal ID proving U.S. citizenship. A group of Arizona residents and nonprofit organizations, including the Inter Tribal Council of Arizona, sued, arguing this conflicted with a federal law requiring states to accept the standard federal form.
The question before the Court
Could Arizona reject a federal voter-registration form just because the applicant didn't attach separate paperwork proving citizenship?
Why it matters
Arizona residents who register using the national mail-in form can do so with a sworn statement of citizenship rather than hunting down a passport or birth certificate. Other states with similar documentary-proof laws must now review whether those rules survive when applied to the federal form, and the ruling shapes how far states can go in policing federal election paperwork.
What changes now
This is a final merits ruling, not a temporary order. Arizona remains barred from demanding extra citizenship documents from applicants who use the federal form, but it can renew its request to the Election Assistance Commission to add a documentary-proof instruction to that form, and can challenge a denial in court under the Administrative Procedure Act. Arizona's own state-specific registration form, which already demands such documents, is unaffected.
What this does not decide
The Court did not decide whether Congress has any general power to set who is qualified to vote in federal elections -- it said that power belongs to the states. It also left open whether Arizona could eventually get its documentary-proof requirement added to the federal form through the Election Assistance Commission or a court challenge to that agency's inaction.
Concurrences and dissents
How the Justices voted
Majority (1). Justice Scalia (author).
Dissent (2). Justice Thomas (author).
Concurrence — Justice Kennedy
Justice Kennedy agreed the National Voter Registration Act unambiguously pre-empts Arizona's law, but rejected the majority's suggestion that the usual presumption against reading federal law to displace state authority doesn't apply to laws passed under the Elections Clause. He argued states' interest in running elections deserves the same respect regardless of which constitutional power Congress used, so he joined the judgment and the rest of the opinion but not that discussion.
Dissent — Justice Thomas
Justice Thomas argued the Constitution gives states the exclusive power to set voter qualifications and to verify them, so requiring Arizona to register anyone who merely signs the federal form without proof of citizenship raises serious constitutional problems. He would have read "accept and use" narrowly, letting Arizona treat the federal form as just one part of its process while still demanding its own proof-of-citizenship documents. Read the full dissent →
Dissent — Justice Alito
“The Court reads an ambiguous federal statute in a way that brushes aside the constitutional authority of the States and produces truly strange results.”Alito's opening objection to the majority's interpretation of the federal voter-registration law.
Justice Alito argued the Court should have applied a presumption against reading the National Voter Registration Act to override Arizona's constitutional authority over election administration, and that the better reading of "accept and use" lets states treat the federal form as one part of, not the entirety of, the registration process. He warned the majority's approach produces the strange result that a voter's citizenship-proof duty depends on which of two forms he happens to fill out. Read the full dissent →
How the Court got there
The legal reasoning, step by step
- The Court read the phrase "accept and use" the federal form, found in the National Voter Registration Act, against its surrounding text rather than in isolation, since ordinary usage of that phrase in a government mandate implies the form must be treated as sufficient on its own, not merely received.
- Comparing the challenged law to a related provision requiring states to register any applicant whose "valid voter registration form" is timely submitted, the Court concluded a completed federal form must count as valid, which is hard to square with Arizona demanding extra documents before accepting it.
- The Court declined to apply the usual presumption against reading federal law to override state authority, reasoning that when Congress acts under the Elections Clause -- the constitutional provision letting Congress override state rules for how federal elections are run -- pre-emption of state election rules is exactly what that power is for.
- The Court agreed that the Constitution gives states, not Congress, the power to decide who is qualified to vote, so a federal law that left a state no way to verify citizenship would raise serious constitutional problems requiring the Court to choose a saving interpretation if one were reasonably available.
- The Court avoided that difficulty by pointing out that the same federal law lets the elections agency add state-specific proof requirements to the form, and lets a state sue under ordinary administrative law if the agency refuses, so Arizona still has a route to enforce its citizenship rule without the state itself being permitted to add new paperwork demands on top of the federal form.
Doctrinal impact
Cases affected by this decision
Reaffirms Ex parte Siebold (100 U.S. 371)
The Court relies on Siebold's rule that valid federal election laws automatically override conflicting state election rules.
Distinguishes United States v. Gradwell (243 U.S. 476)
The Court says this case about a fraud statute has nothing to do with interpreting pre-emption of state election law.