Since Donald Trump’s second inauguration on January 20, 2025, California has filed more than 60 lawsuits against his administration, and the state has won preliminary relief in the large majority of cases where it sought early court orders. The California lawsuits against Trump have targeted birthright citizenship, tariffs, National Guard deployments in Los Angeles, federal funding freezes, mass federal firings, climate rules, and a March 2026 executive order on elections. Governor Gavin Newsom and Attorney General Rob Bonta lead the effort, backed by $50 million the Legislature approved in a special session: $25 million for the AG’s federal litigation and $25 million for legal services for immigrants.1CalMatters. California Trump Lawsuits2Speaker of the Assembly. California Assembly Approves $50M to Protect State Policies From Trump Plans3Orange County Government. California Special Session Funding Details
Nearly every case has been brought with other Democrat-led states, in coalitions ranging from five states on welfare funding to 24 on election rules. By January 2026, Bonta’s office counted 54 lawsuits filed; by spring 2026 the total had passed 60.1CalMatters. California Trump Lawsuits4California Attorney General. Attorney General Bonta Marks One Year Holding Trump Accountable
Birthright Citizenship
California filed the first lawsuit of the second term on January 21, 2025, one day after inauguration. A coalition of 18 state attorneys general, co-led by California, New Jersey, and Massachusetts, challenged an executive order that would have denied U.S. citizenship to children born in the country to undocumented parents. The suit argued the order violated the Fourteenth Amendment’s Citizenship Clause and the Immigration and Nationality Act, and pointed to the Supreme Court’s 1898 ruling in United States v. Wong Kim Ark.5California Attorney General. Attorney General Bonta Sues Trump Administration Over Unconstitutional Executive Order
The order never took effect. Multiple federal judges enjoined it before its February 19, 2025 start date, and the First Circuit upheld the block. A related ACLU class action, Barbara v. Donald J. Trump, secured nationwide class certification in July 2025. As of early 2026, the order remains blocked and the Supreme Court has agreed to hear oral argument in the ACLU case.6ACLU. Trump’s Birthright Citizenship Executive Order: What Happens Next4California Attorney General. Attorney General Bonta Marks One Year Holding Trump Accountable
Tariffs
On April 16, 2025, Newsom and Bonta filed State of California v. Trump in the Northern District of California, challenging the president’s use of the International Emergency Economic Powers Act (IEEPA) to impose broad tariffs on imports from China, Canada, Mexico, and other trading partners. The state argued the tariffs exceeded IEEPA and infringed Congress’s exclusive power to tax imports.7Civil Rights Litigation Clearinghouse. State of California v. Trump
Judge Jacqueline Scott Corley dismissed the California case in June 2025 for lack of jurisdiction, finding it belonged in the Court of International Trade, and California appealed to the Ninth Circuit. That appeal was stayed while the Supreme Court took up two parallel cases. On February 20, 2026, in the consolidated Learning Resources, Inc. v. Trump and Trump v. V.O.S. Selections, Inc., the Court ruled 6-3 that IEEPA does not authorize the president to impose tariffs. Chief Justice Roberts wrote that the statute contains no reference to tariffs or duties and that imposing them is a “core congressional power of the purse” Congress would not delegate without explicit language. Justices Thomas, Kavanaugh, and Alito dissented. The ruling struck down 25% duties on Canadian and Mexican imports and a 10% duty on goods from China and other trading partners.8Supreme Court of the United States. Learning Resources, Inc. v. Trump, No. 24-12879SCOTUSblog. A Breakdown of the Court’s Tariff Decision
Newsom called for immediate refund checks to importers after the ruling, saying the tariffs had collected over $130 billion from businesses and cost the average family an estimated $1,751 over the prior year.10Office of Governor Gavin Newsom. Governor Newsom Calls for Immediate Tariff Refund Checks
National Guard in Los Angeles
In June 2025, Secretary of Defense Pete Hegseth ordered two waves of 2,000 California National Guard members each into Los Angeles in response to protests over federal immigration enforcement. Newsom sued on June 9, 2025, arguing the federalization was carried out without his consent and exceeded 10 U.S.C. § 12406.11Washington Post. California Newsom Trump Lawsuit National Guard12Civil Rights Litigation Clearinghouse. Newsom v. Trump
District Judge Charles R. Breyer issued a temporary restraining order on June 12, 2025, calling the federalization illegal. The Ninth Circuit granted an emergency stay the same day, and in a June 19 opinion a three-judge panel found that the president had likely acted within his authority given evidence of violence against federal officers.13U.S. Court of Appeals for the Ninth Circuit. Newsom v. Trump, No. 25-3727
Judge Breyer kept working the case. On September 2, 2025, he ruled that the federalized Guard’s participation in ICE-related operations violated the Posse Comitatus Act, and he enjoined the administration from using the Guard or Marines to conduct arrests, searches, seizures, security patrols, or crowd control in California.14PBS NewsHour. Judge Says Trump’s Use of National Guard During Los Angeles Immigration Protests Is Illegal15Office of Governor Gavin Newsom. Governor Newsom Secures Federal Court Victory In December 2025 he granted a preliminary injunction ordering an end to the federalization entirely, finding the statutory preconditions were no longer met.16Courthouse News Service. Judge Orders End of National Guard Deployment in LA
A parallel Illinois case finished the fight. On December 23, 2025, in Trump v. Illinois, the Supreme Court denied the administration’s stay request 6-3, holding that “regular forces” in § 12406 means active-duty military and that the president must first show he cannot execute the law using them before federalizing the Guard. Chief Justice Roberts joined Justices Sotomayor, Kagan, Barrett, and Jackson in the majority; Justice Kavanaugh concurred on narrower grounds; Justices Alito, Thomas, and Gorsuch dissented.17Supreme Court of the United States. Trump v. Illinois, 25A44318Just Security. Trump v. Illinois Supreme Court Analysis On December 31, 2025, the Ninth Circuit vacated its earlier stay, Trump announced he would abandon efforts to deploy the Guard over the objections of California, Illinois, and Oregon officials, and Newsom directed state leadership to send the soldiers home.19Office of Governor Gavin Newsom. Federal Court Finally Ends Illegal Federalization of National Guard
Federal Funding Freezes
A large share of the second-term lawsuits target attempts by the executive branch to freeze, withhold, or claw back money Congress had already appropriated. The common argument is that the president cannot unilaterally refuse to spend appropriated funds.
The $3 Trillion Governmentwide Freeze
In early 2025, the administration moved to freeze up to $3 trillion in federal funding nationwide. A 23-state coalition led by California secured a temporary restraining order from a federal court in Rhode Island, then a preliminary injunction on March 6, 2025. California alone stood to lose roughly $168 billion in annual federal funds, about 34% of the state budget, including $107.5 billion for Medicaid programs serving 14.5 million residents.20California Attorney General. Attorney General Bonta Secures Preliminary Injunction Against Trump
Welfare and Child Care
On January 8, 2026, California joined New York, Colorado, Illinois, and Minnesota in suing over a freeze of more than $10 billion in welfare-related funding, including $7.35 billion in Temporary Assistance for Needy Families, $2.4 billion in the Child Care and Development Fund, and $869 million in the Social Services Block Grant. California’s share was roughly $5 billion. The administration cited fraud concerns; the states argued no evidence had been produced and that the freeze was being used to punish Democrat-led states. A federal judge in the Southern District of New York issued a temporary restraining order on January 9, 2026.21California Attorney General. Attorney General Bonta Sues Trump Administration to Block Unlawful Freeze of $10 Billion22Courthouse News Service. Trump Administration Blocked From $10 Billion Welfare Funding Freeze
Electric Vehicle Charging
On May 7, 2025, California co-led a 17-state challenge to the Federal Highway Administration’s suspension of the $5 billion National Electric Vehicle Infrastructure (NEVI) program, funded under the Infrastructure Investment and Jobs Act. The case, State of Washington v. U.S. Department of Transportation, produced a preliminary injunction in June 2025 and a final summary judgment for the states in January 2026, permanently barring the administration from withdrawing states’ funds, canceling implementation plans, or otherwise interfering with the program.23Office of Governor Gavin Newsom. California Sues Trump Administration for Illegally Withholding Billions in Bipartisan Infrastructure Funds24Civil Rights Litigation Clearinghouse. State of Washington v. U.S. Department of Transportation
Clean Energy and Hydrogen
On February 18, 2026, a 13-state coalition filed California v. Wright in the Northern District of California, challenging the termination of billions in clean-energy funding under the Inflation Reduction Act and the Bipartisan Infrastructure Law. Targeted programs include the $8 billion Regional Clean Hydrogen Hubs Program and the $3 billion Grid Resilience and Innovation Partnerships Program. California’s Alliance for Renewable Clean Hydrogen Energy Systems (ARCHES) stood to lose $1.2 billion. The complaint alleges violations of the Administrative Procedure Act, separation of powers, and the First and Fifth Amendments. The case is pending.25Los Angeles Times. California Sues Trump Administration Over Billions in Canceled Clean Energy Funding26New York Attorney General. California et al. v. Wright et al., Complaint
Federal Workforce and DOGE
California has attacked the administration’s mass termination of federal employees from more than one angle. On March 6, 2025, Bonta joined a 20-state coalition arguing that Office of Personnel Management directives to fire probationary employees across agencies exceeded statutory authority, violated the Administrative Procedure Act’s Reduction in Force procedures, and skipped the 60 days of advance notice states are owed before mass layoffs.27California Attorney General. Attorney General Bonta Continues His Support of Federal Workers
Santa Clara and San Francisco counties joined a separate coalition of cities, counties, and labor unions challenging workforce cuts driven by the Department of Government Efficiency (DOGE), headed by Elon Musk. In May 2026, Judge Susan Illston in the Northern District of California granted a preliminary injunction pausing further reductions in force and executive branch reorganization for the duration of the case, writing that “a President may not initiate large-scale executive branch reorganization without partnering with Congress.” The administration appealed to the Ninth Circuit.28NBC Bay Area. Santa Clara, San Francisco Trump DOGE Lawsuit29CNBC. Judge Blocks Trump Federal Workforce Cuts
In October 2025, Judge Illston issued another order in a case brought by the American Federation of Government Employees, blocking the administration from issuing reduction-in-force notices during a government shutdown and noting that the layoffs appeared “unlawfully targeted at Democrats.”30Politico. Trump Administration Layoffs Order
Climate: The Endangerment Finding Repeal
On March 19, 2026, a 24-state coalition led by the attorneys general of California, Connecticut, Massachusetts, and New York filed suit in the U.S. Court of Appeals for the D.C. Circuit challenging the EPA’s February 2026 repeal of the 2009 “Endangerment Finding,” the scientific determination that greenhouse gases endanger public health. That finding is the legal foundation for virtually all federal greenhouse gas regulation. The coalition argues the repeal is scientifically baseless and legally flawed. The case is active.31Spectrum News. California Pollution Lawsuit Against Trump Administration32Office of Governor Gavin Newsom. California Is Taking Donald Trump to Court
Elections Executive Order
On April 3, 2026, California co-led a 24-jurisdiction coalition challenging a March 31 executive order that would direct the U.S. Postal Service to deliver mail-in ballots only to voters on a federally approved list, require unique barcodes on ballot envelopes, and threaten election officials with criminal prosecution for sending ballots to anyone else. The lawsuit was filed in the U.S. District Court for the District of Massachusetts. It argues the president lacks constitutional authority to regulate state elections and that the order would disenfranchise voters and force states to abandon established procedures. The coalition noted that the federal database the order relies on had a 35% error rate in at least one county review. The case is pending.33California Attorney General. Attorney General Bonta Co-Leads Lawsuit Challenging President Trump’s Executive Order on Elections34Massachusetts Attorney General. AG Campbell Sues Trump Administration Over Unlawful Executive Order
How California Has Been Winning
The suits rest on a short list of recurring legal theories: that the challenged action violates the Administrative Procedure Act by skipping required rulemaking, exceeds the powers Congress granted the president, or breaches the constitutional separation of powers. As of August 2025, Bonta’s office reported spending roughly $5 million of its $25 million allocation, filing 37 lawsuits and leading or co-leading 23 of them, and winning preliminary relief in 17 of the 19 cases where it sought early orders.35KCRA. Money California Spent on Lawsuits Against Trump Administration36California Attorney General. Six Months of the Second Trump Administration
The outlook at the Supreme Court is mixed. The Court struck down the IEEPA tariffs and refused to let the Illinois National Guard federalization stand, but analysts have noted that the current majority has “consistently voted 6-3 to uphold elements of the Trump agenda” in other areas, and recent rulings narrowing federal regulatory authority could cut against California in climate and workforce cases still working their way up.37CalMatters. Donald Trump California Lawsuits