Moore v. Harper
The Supreme Court rejected the 'independent state legislature theory,' ruling that state legislatures must still follow their state constitutions when drawing congressional districts and setting federal election rules, and that state courts can strike down those rules for violating state constitutional provisions.
The decision was a significant check on state legislative power over elections, though the Court also warned that state courts cannot go so far in reviewing election laws that they effectively take over the role the Constitution assigns to state legislatures.
How it got here: The North Carolina Supreme Court struck down the legislature's 2021 congressional map; the legislature sought an emergency stay from the Supreme Court (denied), which then agreed to hear the case on the merits.
The Case in Depth
What happened
After the 2020 census gave North Carolina an extra congressional seat, the Republican-controlled General Assembly drew a new congressional map. Voter groups and conservation organizations sued in state court, arguing the map was an unconstitutional partisan gerrymander under the North Carolina Constitution. The North Carolina Supreme Court agreed, struck down the map, and ruled that the federal Elections Clause did not shield the legislature's redistricting decisions from state court oversight. The legislature then asked the U.S. Supreme Court to reverse that ruling.
The question before the Court
Does the U.S. Constitution's Elections Clause free state legislatures from having to follow their own state constitutions — and from review by state courts — when they draw congressional maps and set other rules for federal elections?
The Court's answer
No — the Elections Clause does not give state legislatures the power to set federal election rules free from their state constitutions or state court review. The Court held that when state legislatures exercise their Elections Clause authority, they are still ordinary lawmaking bodies created by and bound by their state constitutions, just as when they pass any other kind of law. A long history of judicial review — predating the Constitution itself — makes clear that legislatures cannot escape constitutional oversight simply because their power on a particular subject comes from federal law. Both the state and federal constitutions constrain what a state legislature can do.
The Court also recognized a limit running the other direction: state courts cannot stretch their interpretation of state law so far as to effectively seize the election-regulating role the Constitution specifically assigns to state legislatures. The Court declined to adopt a precise legal test for policing that boundary, and it did not decide whether North Carolina's courts had crossed it — the legislature had not properly raised that argument.
Curious how the Court got there? See the step-by-step legal reasoning →
Why it matters
State courts across the country retain the power to strike down congressional redistricting maps and federal election rules that violate their state constitutions. Partisan gerrymandering claims that federal courts cannot hear may still be reviewable under state law. Legislatures hoping to draw maps immune from any state-level review will find no cover in the federal Elections Clause.
What changes now
With the North Carolina Supreme Court's Harper I ruling affirmed, the 2021 congressional maps remain enjoined. North Carolina must draw replacement maps under state and federal law. More broadly, the ruling confirms that state courts nationwide can use their state constitutions to review congressional redistricting plans and other federal election rules. The Court left open for a future case the precise legal standard for when state court review goes too far and unconstitutionally encroaches on state legislative authority.
What this does not decide
The Court did not decide whether North Carolina's Supreme Court itself overstepped in reading the state constitution to prohibit partisan gerrymandering — that argument was not properly raised. The ruling also does not establish what specific legal test federal courts should use when reviewing state court election decisions, nor does it settle whether partisan gerrymandering claims are winnable under any particular state constitution.
Concurrences and dissents
Concurrence — Justice Kavanaugh
Justice Kavanaugh joined the majority in full but wrote separately to press for a specific legal standard federal courts should use when reviewing state court election decisions. In his view, Chief Justice Rehnquist's formulation from Bush v. Gore — asking whether a state court 'impermissibly distorted' state law 'beyond what a fair reading required' — is the right test. He agreed the Court did not need to adopt that standard in this case because the legislature had disclaimed any challenge to the North Carolina courts' reading of state law, but urged the Court to formalize the Rehnquist standard in a future case.
Dissent — Justice Thomas
Justice Thomas, joined in full by Justice Gorsuch and joined as to Part I by Justice Alito, would have dismissed the case as moot without reaching the merits. After the North Carolina Supreme Court overruled Harper I on state-law grounds and dismissed all claims in the legislature's favor (Harper III), he argued the Elections Clause defense could no longer affect any live judgment — making the majority's ruling an advisory opinion forbidden by Article III. On the merits (Part II, joined only by Gorsuch), Thomas argued the Elections Clause conveys a purely federal power that transcends state constitutional limits: prior cases like Smiley and Hildebrant addressed only who constitutes the state 'Legislature,' not whether the people of a state can impose substantive limits on what laws that legislature can make for federal elections. He also warned (Part III) that the majority's framework would draw federal courts into unprincipled, politically charged supervision of state constitutional interpretation.
How the Court got there
The legal reasoning, step by step
- The Court started from the deep historical roots of judicial review — the power of courts to strike down legislative acts that violate a constitution. State courts had been doing this before the 1787 Constitutional Convention, and the practice was so well-established by the time Marbury v. Madison was decided in 1803 that Chief Justice Marshall called it a 'fundamental principle' of American government, not a new invention.
- Three prior Supreme Court cases established the core rule. In Hildebrant (1916), the Court upheld Ohio voters' power to block a congressional redistricting law through a state referendum, rejecting the argument that the Elections Clause made that unconstitutional. In Smiley v. Holm (1932), the Court held unanimously that Minnesota's legislature had to respect the governor's veto when redistricting, because nothing in the federal Constitution lets state legislatures make election laws 'in any manner other than that in which the constitution of the State has provided.'
- In Arizona State Legislature v. Arizona Independent Redistricting Commission (2015), the Court reaffirmed the same core principle: whatever body draws congressional maps, it remains subject to constraints in the state constitution. The Elections Clause contains no instruction, and the Court had never held, that a state legislature may defy its own state constitution when setting federal election rules.
- The Court rejected the legislature's main argument — that because the Elections Clause delegates a federal power, only the U.S. Constitution can limit how that power is exercised. State legislatures are 'creatures of' their state constitutions; they exist because of those documents and are bound by them. When they regulate federal elections, they act under two sets of constraints simultaneously: the state constitution and the federal one. Both apply.
- The Court also rejected the proposed distinction between 'procedural' state constitutional limits on the legislature (like requiring a governor's veto, which everyone conceded was allowed) and 'substantive' ones (like a prohibition on partisan gerrymandering). Neither Smiley nor Hildebrant drew that line, and the Court found the boundary between procedure and substance too contested and fuzzy to provide a workable rule.
- The Court added an important caveat: state courts themselves do not have unlimited power. They may not interpret state law so expansively that they effectively arrogate to themselves the election-regulating authority the Constitution assigns to state legislatures. The Court declined to adopt a specific test for when that line is crossed, however, and expressly declined to decide whether North Carolina's Supreme Court had crossed it, because the legislature had not meaningfully raised that argument.
Doctrinal impact
Cases affected by this decision
Reaffirms Smiley v. Holm (285 U.S. 355)
State legislatures must follow state constitutional procedures when making federal election laws; this principle commands continued respect.
Reaffirms Ohio ex rel. Davis v. Hildebrant (241 U.S. 565)
State constitutional provisions — including a popular referendum — can lawfully check a legislature's redistricting power under the Elections Clause.
Reaffirms Arizona State Legislature v. Arizona Independent Redistricting Comm'n (576 U.S. 787)
Whatever body draws congressional maps, it must still follow the constraints set in the state constitution.
Distinguishes McPherson v. Blacker (146 U.S. 1)
That case did not address any conflict between a state constitution and a state legislature, so it does not support exempting legislatures from state court review.