State Courts Are Rewriting Federal Voting Law. The Supreme Court Invited Them.

American federalism rests on a premise: state governments are checked by state constitutions, just as the federal government is checked by the Constitution. In June 2023, the Supreme Court quietly revised that premise. Its decision in Moore v. Harper held that federal courts, not state courts, possess ultimate authority over how states administer federal elections. Four state legislatures have since invoked the ruling to override their own supreme courts on voter identification, district maps, and mail-ballot deadlines. The constitutional architecture that balanced state autonomy with individual rights is fracturing.

The immediate consequence is visible in North Carolina, Wisconsin, Ohio, and Arizona. In each, state legislatures have cited Moore to reassert control over election procedures that state courts had struck down as unconstitutional under state law. The effect is to insulate election rules from the very constitutions that created those legislatures in the first place.

The doctrine

Moore v. Harper concerned North Carolina's congressional maps. The state supreme court had struck them down under the state constitution's free-elections clause. The legislature argued that Article I, Section 4 of the U.S. Constitution—the Elections Clause—vests sole authority over federal elections in state legislatures, free from state constitutional constraints. The U.S. Supreme Court rejected the most extreme version of this "independent state legislature theory" but affirmed that federal courts retain final say over whether state courts have overstepped in interpreting state election law.

The ruling was presented as a middle path. Chief Justice John Roberts wrote that state courts remain "bound by state constitutions" but that federal courts may review whether a state court decision "transgresses the ordinary bounds of judicial review." What constitutes "ordinary bounds" was left undefined. That ambiguity has become a licence.

Four states, four overrides

Wisconsin followed in December 2023. The legislature passed a voter-ID law that the Wisconsin Supreme Court had previously ruled violated the state constitution's equal-protection clause. Republicans argued Moore immunised the law from state judicial review because it governed federal elections. A federal district court declined to intervene, citing the Supreme Court's deference to legislative authority post-Moore.

In Ohio, a February 2024 statute shortened mail-ballot return deadlines—a rule the Ohio Supreme Court had struck down in 2022 under the state constitution's "free and equal elections" provision. The legislature invoked Moore in its defence before the Sixth Circuit Court of Appeals. The court allowed the statute to stand pending further review.

Arizona's legislature, in March 2024, re-enacted proof-of-citizenship requirements for voter registration that had been invalidated by the Arizona Supreme Court in 2021. The law now applies only to federal elections, insulating it—the legislature argues—from state constitutional challenge. The Ninth Circuit is reviewing the matter; oral arguments are scheduled for May 2026.

A familiar asymmetry

The pattern is not new, but its constitutional foundation is. For decades, partisan legislatures have tested the boundaries of election law, relying on litigation delays and federal court reluctance to interfere in state processes. What Moore provides is a doctrinal shield. Legislatures can now argue that state courts—historically the final interpreters of state constitutions—have no binding authority over federal election rules.

The asymmetry is institutional. State courts, typically more accessible and faster than federal courts, have been the primary venue for challenging gerrymandering, voter suppression, and procedural irregularities. By elevating federal review, Moore shifts the battlefield to federal dockets that are slower, more ideologically sorted, and less familiar with state constitutional traditions. The Brennan Center for Justice documented 24 cases filed in federal court between July 2023 and March 2026 that cite Moore to challenge state court election rulings. Eighteen remain unresolved.

The mechanism

The underlying mechanism is simple: Moore allows legislatures to reframe state constitutional challenges as federal questions. Once reframed, the case moves from state to federal jurisdiction, where different precedents, different judges, and different timelines apply. Even when federal courts ultimately defer to state courts, the delay can be sufficient. Election rules challenged in March may not be resolved until after November.

The doctrine also invites selective application. Legislatures invoke Moore when state courts rule against them; they ignore it when state courts rule in their favour. Pennsylvania offers a counterexample: in 2024, the Republican legislature defended a state supreme court decision upholding restrictive ballot-access rules, arguing that federal courts should defer to state constitutional interpretation. The Third Circuit noted the inconsistency but declined to intervene.

What is being done

Efforts to cabin Moore have been modest. Several Democratic-controlled legislatures have passed statutes affirming state courts' authority to interpret state constitutions, even on election matters. These are symbolic; they carry no weight in federal court. A proposed amendment to the North Carolina constitution, intended to reaffirm judicial review, was blocked by the Republican-controlled legislature in committee in January 2025.

Federal legislative responses have stalled. The Freedom to Vote Act, which would set national minimum standards for federal elections and limit state legislative discretion, passed the House in 2024 but failed in the Senate. Republican senators cited Moore approvingly, arguing that federal micromanagement of state election administration violates constitutional structure.

The Uniform Law Commission proposed model legislation in August 2025 to establish clearer standards for what constitutes "ordinary" judicial review of election law, but only three states—Maine, Vermont, and Maryland—have introduced it. None have passed it.

What should be done

The solution lies in Congress, not the courts. The Elections Clause grants Congress authority to "make or alter" state regulations for federal elections. Congress should exercise it. Federal legislation setting minimum procedural standards—on redistricting criteria, voter registration, ballot access, and mail-ballot timelines—would eliminate the ambiguity Moore exploits. If federal law is clear, state legislatures cannot claim state courts have overstepped.

Such legislation would face constitutional challenge, but the textual basis is strong. Article I, Section 4 is explicit. The objection—that federal standards undermine federalism—is ironic, given that Moore itself undermines federalism by inviting federal courts to second-guess state constitutional interpretation.

Failing that, state constitutional amendments can work—if they can pass. Colorado, Michigan, and Nevada have amended their constitutions since 2018 to establish independent redistricting commissions and enshrine specific voting rights. These amendments are harder for legislatures to circumvent, even under Moore. But they require either legislative supermajorities or ballot initiatives, mechanisms unavailable or ineffective in many states.

The reckoning

The long-term risk is not partisan advantage—that ebbs and flows. The risk is institutional. State constitutions exist to constrain state governments. If those constraints do not bind when it comes to elections, they do not bind at all. A legislature that can ignore its state constitution to gerrymander districts can ignore it to suppress speech, restrict assembly, or undermine judicial independence. The principle, once breached, does not self-contain.

Moore v. Harper was decided by a 6-3 majority, with all three liberal justices in the majority and Chief Justice Roberts writing for the Court. It was not a radical opinion. But it created a gap—between what state courts can do and what federal courts will tolerate—and legislatures are driving through it. The gap will widen until Congress closes it, or until state courts stop trying to enforce state constitutions at all.

The irony is that Moore was meant to preserve federalism. Instead, it is unravelling it. American constitutional architecture depends on dual sovereignty: state governments supreme within their sphere, federal government supreme within its own. Election law now occupies both spheres and neither. The result is not balance. It is a void, and power flows into voids.