Republicans and Democrats squared off in court Monday in a high-stakes battle over the fate of California’s Proposition 50, which reconfigures the state’s congressional districts and could ultimately help determine which party controls the U.S. House in the 2026 midterms.
Dozens of California politicians and Sacramento insiders — from GOP Assembly members to Democratic redistricting expert Paul Mitchell — have been called to testify in a Los Angeles federal courtroom over the next few days.
The GOP wants the three-judge panel to temporarily block California’s new district map, claiming it is unconstitutional and illegally favors Latino voters.
An overwhelming majority of California voters approved Prop. 50 on Nov. 4 after Gov. Gavin Newsom pitched the redistricting plan as a way to counter partisan gerrymandering in Texas and other GOP-led states. Democrats admitted the new map would weaken Republicans’ voting power in California, but argued it would just be a temporary measure to try to restore national political balance.
Attorneys for the GOP cannot challenge the new redistricting map on the grounds that it disenfranchises swaths of California Republicans. In 2019, the U.S. Supreme Court decided that complaints of partisan gerrymandering have no path in federal court.
But the GOP can bring claims of racial discrimination. They argue California legislators drew the new congressional maps based on race, in violation of the Equal Protection Clause of the 14th Amendment and the 15th Amendment, which prohibits governments from denying citizens the right to vote based on race or color.
On Monday, attorneys for the GOP began by homing in on the new map’s Congressional District 13, which currently encompasses Merced, Stanislaus, and parts of San Joaquin and Fresno counties, along with parts of Stockton.
When Mitchell drew up the map, they argued, he over-represented Latino voters as a “predominant consideration” over political leanings.
They called to the stand RealClearPolitics elections analyst Sean Trende, who said he observed an “appendage” in the new District 13, which extended partially into the San Joaquin Valley and put a crack in the new rendition of District 9.
“From my experience [appendages] are usually indicative of racial gerrymandering,” Trende said. “When the choice came between politics and race, it was race that won out.”
Republicans face an uphill struggle in blocking the new map before the 2026 midterms. The hearing comes just a few weeks after the U.S. Supreme Court allowed Texas to temporarily keep its new congressional map — a move that Newsom’s office says bodes poorly for Republicans trying to block California’s map.
“In letting Texas use its gerrymandered maps, the Supreme Court noted that California’s maps, like Texas’s, were drawn for lawful reasons,” Brandon Richards, a spokesperson for Newsom, said in a statement. “That should be the beginning and the end of this Republican effort to silence the voters of California.”
In Texas, GOP leaders drew up new congressional district lines after President Trump openly pressed them to give Republicans five more seats in the U.S. House of Representatives. A federal court blocked the map, finding racial considerations likely made the Texas map unconstitutional. But a few days later the Supreme Court granted Texas’ request to pause that ruling, signaling they view the Texas case, and this one in California, as part of a national politically-motivated redistricting battle.
“The impetus for the adoption of the Texas map (like the map subsequently adopted in California),” Justice Samuel A. Alito Jr. argued, “was partisan advantage pure and simple.”
The fact that the Supreme Court order and Alito’s concurrence in the Texas case went out of their way to mention California is not a good sign for California Republicans, said Richard L. Hasen, professor of law and director of the Safeguarding Democracy Project at UCLA School of Law.
“It’s hard to prove racial predominance in drawing a map — that race predominated over partisanship or other traditional districting principles,” Hasen said. “Trying to get a preliminary injunction, there’s a higher burden now, because it would be changing things closer to the election, and the Supreme Court signaled in that Texas ruling that courts should be wary of making changes.”
Many legal scholars argue that the Supreme Court’s ruling on the Texas case means California will likely keep its new map.
“It was really hard before the Texas case to make a racial gerrymandering claim like the plaintiffs were stating, and it’s only gotten harder in the last two weeks,” said Justin Levitt, a professor of law at Loyola Marymount University.
Hours after Californians voted in favor of Prop. 50 on Nov. 4, Assemblymember David J. Tangipa (R-Fresno) and the California Republican Party filed a lawsuit alleging that the map enacted in Prop. 50 for California’s congressional districts is designed to favor Latino voters over others.
The Department of Justice also filed a complaint in the case, arguing the new congressional map uses race as a proxy for politics and manipulated district lines “in the name of bolstering the voting power of Hispanic Californians because of their race.”
Mitchell, the redistricting expert who drew up the maps, is likely to be a key figure in this week’s battle. In the days leading up to the hearing, attorneys sparred over whether Mitchell would testify and whether he should turn over his email correspondence with legislators. Mitchell’s attorneys argued he had legislative privilege.
Attorneys for the GOP have seized on public comments made by Mitchell that the “number one thing” he started thinking about” was “drawing a replacement Latino majority/minority district in the middle of Los Angeles” and the “first thing” he and his team did was “reverse” the California Citizens Redistricting Commission’s earlier decision to eliminate a Latino district from L.A.
Some legal experts, however, say that is not, in itself, a problem.
“What [Mitchell] said was, essentially, ‘I paid attention to race,’” Levitt said. “But there’s nothing under existing law that’s wrong with that. The problem comes when you pay too much attention to race at the exclusion of all of the other redistricting factors.”
Other legal experts argue that what matters is not the intent of Mitchell or California legislators, but the California voters who passed Prop. 50.
“Regardless of what Paul Mitchell or legislative leaders thought, they were just making a proposal to the voters,” said Hasen, who filed an amicus brief in support of the state. “So it’s really the voters’ intent that matters. And if you look at what was actually presented to the voters in the ballot pamphlet, there was virtually nothing about race there.”
