Supreme Court blocks Trump-backed Missouri congressional map

In a case watched across the country and as voting begins in the midterm elections, the Supreme Court blocked a congressional map in Missouri that was aimed at netting Republicans another seat in the U.S. House.

This is the third time the high court has blocked the redistricting plan that could have helped ousted Democratic Congressman Emanuel Cleaver by increasing the number of Republican voters in his district.

The court warned that changing maps now would cause "electoral chaos." The decision requires the state use the same districts provided to voters in 2022 and 2024. That's even though a different map was used in the primaries there last month.

It comes after weeks of conflicting rulings in state courts and federal courts. Elections officials in Missouri already started mailing some absentee ballots last week using the old districts and some argued it would be too late to change them.

Missouri lawmakers passed the new map last year at the behest of Trump. It was part of his nationwide strategy to draw more GOP-leaning seats to prevent Republicans from losing the House.

A citizen petition makes the redistricting subject to voter approval

Usually, states redistrict at the start of each decade. The redistricting battle set off by Trump ended with the GOP besting the Democrats by tilting about nine or 10 more districts, including Missouri's fifth district, their way. Republicans currently only hold a few seats' advantage in the House.

But opponents of the new Missouri map successfully gathered citizen signatures to put it to a vote on the November ballot.

The Missouri Supreme Court ruled earlier this month that the ballot question meant the 2025 GOP-backed map never went into effect and was never law – even though it had been used in the Aug. 4 primaries. The state's high court blamed Republican Secretary of State Denny Hoskins for proceeding with the GOP map in the primaries even though it hadn't been approved by voters.

The U.S. Supreme Court in its ruling today backed that up, noting that the state court had said in May - before the primary - that the GOP map would require voter approval before it could be used.

The U.S. Supreme Court had declined on Sept. 10 to intervene in the state court's ruling but allowed the case to continue.

Simultaneously, Republicans sued in federal court and won backing for the GOP map from a federal judge and then, last week, a federal appeals court. That sent the case back to the U.S. Supreme Court, which ruled against Republican lawmakers today.

In general, Republicans argued that their map should be used because more than a million Missourians cast votes in the primary using the map. Opponents of redistricting argued voters hadn't approved the map and blamed Republican officials for dragging out the process and of trying to force through the new map.

Jason Rosenbaum covers politics for St. Louis Public Radio.

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