Missouri's Supreme Court upheld a Republican-drawn congressional map on Tuesday in a 4-3 decision, ruling that state law does not explicitly prohibit mid-decade redistricting and that the legislature retains the authority to redraw congressional lines more frequently than once every 10 years. Writing for the four-judge majority, Judge Zel M. Fischer stated: "The obligation to legislate congressional districts once a decade does not limit the General Assembly's power to redistrict more frequently than once a decade. Simply put, 'when' does not mean 'only when.'" Three dissenting justices argued the ruling opened the door to purely political map manipulation divorced from any legitimate governmental purpose. NBC News and The Associated Press confirmed the ruling.

The new congressional map is designed to help Republicans gain a House seat in the 2026 midterm elections by moving portions of Kansas City and its surrounding areas into more rural, Republican-leaning congressional districts — specifically targeting Democratic Representative Emanuel Cleaver's seat. Missouri Republicans argued the map better reflects population changes since the 2020 census and aligns with their legislative mandate. Democrats and the NAACP argued the remapping constitutes a racial and partisan gerrymander that dilutes the voting power of African American voters in the Kansas City area. The NAACP has appealed a separate lawsuit challenging the map's constitutionality under the Voting Rights Act.

Missouri's ruling is one of six states that enacted new congressional maps in 2025 and early 2026, triggering what analysts have called a "redistricting arms race" as Republican-controlled legislatures respond to Trump's public call on GOP states to redraw maps ahead of the midterms. Several blue states have simultaneously considered or enacted their own remedial maps in response, with New York and California exploring modifications to their congressional lines. The political stakes are significant: Republicans currently hold a narrow House majority, and even a handful of seat changes could flip control of the chamber in November.

Voter advocacy groups in Missouri are pursuing a separate citizen referendum to block the new map, collecting signatures for a ballot initiative that would restore the original lines. The referendum effort faces a tight timeline to qualify for the November ballot. The NAACP's federal Voting Rights Act challenge remains pending and could ultimately override the state Supreme Court ruling if a federal court finds the map illegally dilutes minority voting power — a standard that has been tested repeatedly in redistricting battles across the country since the Supreme Court's 2013 decision in Shelby County v. Holder weakened federal preclearance requirements.