The dispute over Missouri’s mid-decade congressional map reached the U.S. Supreme Court this week after Missouri’s high court held that a citizen referendum means the 2025 map never took effect and the state must use the 2022 districts for the November election. Attorneys general from 20 Republican-led states filed a brief asking the Supreme Court to intervene and keep the new map in place.
- Missouri Supreme Court ruled the 2025 congressional map never took effect because a referendum petition was sufficient; the state must use the 2022 map unless the U.S. Supreme Court intervenes.
- Attorney General Catherine Hanaway and 20 Republican-led states asked the U.S. Supreme Court to stay or reverse the Missouri decision to keep the 2025 map in place for the November election.
- Opponents argue the Missouri ruling rests on state law and that the federal courts lack jurisdiction or that Missouri seeks the wrong legal remedy; the timing raises practical ballot-finalization concerns.
What the Missouri courts decided
In a unanimous decision, the Missouri Supreme Court concluded that organizers who submitted a referendum petition satisfied the state constitution’s referendum procedures, and that the statute enacting the 2025 map (HB 1) therefore could not take effect until the voters decide in November. The court ordered that the referendum appear on the ballot and directed Secretary of State Denny Hoskins to use the 2022 congressional map for the upcoming election unless the U.S. Supreme Court acts otherwise.
Federal filings and who is asking for review
Missouri Attorney General Catherine Hanaway has asked the U.S. Supreme Court for emergency relief from the state high court’s ruling. Her office and Missouri’s Solicitor General also pressed arguments in federal district court seeking to block the Missouri Supreme Court order. Separately, attorneys general from 20 Republican-controlled states filed a brief Monday supporting Missouri’s effort to retain the 2025 map for November ballots.
Arguments presented to the high court
- Missouri officials supporting the 2025 map say changing the map now would disrupt the election and disenfranchise voters who already cast ballots under the new boundaries. They argue the state supreme court’s ruling conflicts with the Elections Clause of the U.S. Constitution and that the high court should preserve the map that was used in the primary so the general election can proceed on schedule.
- Opponents, including the referendum organizers People Not Politicians and an individual organizer, told the Supreme Court the state ruling rests on state law and therefore presents no federal question for the U.S. Supreme Court to resolve. They further argued that the remedy Missouri seeks — to have the 2025 map treated as effective despite the referendum — would require an injunction, not merely a stay, and that the state’s arguments are barred by procedural rules or lack standing.
Legal and practical stakes
The dispute arises after the Republican-controlled Missouri Legislature enacted HB 1 in September 2025. That map would, by proponents’ own description, increase Republican representation in the state’s U.S. House delegation. Organizers submitted more than 300,000 signatures in December seeking a statewide referendum to put the map before voters; Secretary Hoskins rejected the petition on Aug. 4, the last day to act, prompting litigation.
The Missouri Supreme Court found the petition legally sufficient, concluding HB 1 never took effect. Missouri officials say the timing creates logistical problems: ballots and election administration are time-sensitive, and state law includes a deadline — identified in press reports — after which local election officials generally cannot add or remove candidates or issues.
Timeline of key events (as reported)
- September 2025 — Missouri Legislature passes HB 1; Governor signs the congressional map into law.
- December 2025 — Organizers submit a referendum petition with over 300,000 signatures seeking to place HB 1 on the November 2026 ballot.
- August 4, 2026 — Secretary of State Denny Hoskins rejects the petition (the same day as Missouri’s primary), prompting a state-court challenge.
- September 3, 2026 — Missouri Supreme Court issues a unanimous opinion finding the petition sufficient and ruling HB 1 did not take effect; it orders the referendum be placed on the November ballot and directs use of the 2022 map unless the U.S. Supreme Court intervenes.
- September 5–7, 2026 — Missouri files emergency requests in federal court and with the U.S. Supreme Court; 20 Republican-led states file a supporting brief at the Supreme Court.
- Early September 2026 — Federal district court and Supreme Court deadlines and filings proceed as parties ask for emergency stays or injunctions; state-level statutory deadlines for finalizing ballots approach.
How the parties justify their positions
Supporters of the 2025 map argue the Missouri Supreme Court’s ruling causes confusion and harms voters who already voted in a primary conducted under the new boundaries. In filings cited by local outlets, Missouri’s solicitors said the state supreme court adopted what they called a “legal fiction” by treating the 2025 map as retroactively invalid for the primary. Attorney General Hanaway has urged the U.S. Supreme Court to step in and reverse or stay the state court’s decision.
Opponents point to longstanding precedent that state courts deciding cases on adequate and independent state-law grounds are generally insulated from U.S. Supreme Court review on those state-law issues. They also contend that Missouri’s requested relief is procedurally inappropriate — that securing authority to use HB 1 would require an injunction with a different legal standard — and that the state lacks standing to press certain federal claims.
Implications for Missouri voters and candidates
Whatever the U.S. Supreme Court decides could determine which congressional map Missouri voters will use this fall and alter the composition of a number of competitive races. Local election officials face tight deadlines for printing ballots and finalizing candidate assignments; Missouri law contains cutoffs after which changes are restricted. That timeline heightens the practical urgency of the legal fight.
Unresolved questions and next steps
- At the time of reporting, it remained unclear whether the U.S. Supreme Court would grant emergency relief or decline review. The Missouri Supreme Court’s opinion relied on state-law grounds, which the state high court indicated largely precluded federal review unless a federal question is properly preserved.
- Federal litigation in the Eastern District of Missouri is ongoing; judges in that court set deadlines for intervenors and may issue decisions quickly because of election-related timing constraints.
- If the U.S. Supreme Court accepts the case, it will confront issues about the interplay between state constitutional referendum powers and the Elections Clause as applied to mid-decade redistricting enacted by state legislatures.
“The Missouri Supreme Court concluded the petition was legal, sufficient, and timely.”
Why this matters beyond Missouri
The case tests a broader question of whether state referendum mechanisms can block legislative redistricting measures for federal elections and how that interacts with the U.S. Constitution’s Elections Clause. Several other states have seen aggressive mid-decade redistricting proposals in recent years, and a high-court ruling could affect the ability of voters or legislatures elsewhere to contest or preserve maps close to federal election dates.
Reporting for this article relied on contemporaneous filings and coverage in Missouri outlets and legal reporting about the case and the amicus brief filed by 20 Republican-led states urging the U.S. Supreme Court to intervene.
