Attorney General Bonta Secures Preliminary Relief Blocking California’s Medicaid Data from Being Used for Immigration Enforcement Purposes

OAKLAND – California Attorney General Rob Bonta today issued the following statement after the U.S. District Court for the Northern District of California granted a preliminary injunction finding California and a multistate coalition were likely to succeed on their claim that the U.S. Department of Health and Human Services’ (HHS) decision to provide unfettered access to individual personal health data to the U.S. Department of Homeland Security (DHS), which houses Immigration and Customs Enforcement (ICE), violated the Administrative Procedure Act’s prohibition on arbitrary and capricious rulemaking. The preliminary injunction blocks DHS from using Medicaid data obtained from plaintiff states for immigration enforcement purposes, and blocks HHS from sharing Medicaid data obtained from coalition states with DHS for immigration enforcement purposes. The preliminary injunction will remain in place either until 14 days after HHS and DHS complete a reasoned decisionmaking process that complies with the Administrative Procedure Act, or until litigation concludes.

“The Trump Administration’s move to use Medicaid data for immigration enforcement upended longstanding policy protections without notice or consideration for the consequences. It sowed a culture of fear that threatens our Medicaid system, caused chaos for states and providers, and created a chilling effect for patients seeking vital emergency medical care,” said Attorney General Bonta. “Today’s preliminary injunction rightfully blocks any sharing of California's Medicaid data for immigration enforcement for now — and ensures any of the data that’s already been shared is not being used for immigration enforcement purposes. As the President continues to overstep his authority in his inhumane anti-immigrant crusade, this is a clear reminder that he remains bound by the law.”

On July 1, 2025, California led a multistate coalition in filing a lawsuit against the Trump Administration arguing that the mass transfer of Medicaid data violates the law and asking the court to block any new transfer or use of this data for immigration enforcement purposes. The lawsuit highlighted that the Trump Administration’s illegal actions are creating fear and confusion leading noncitizens and their family members to disenroll, or refuse to enroll, in emergency Medicaid for which they are otherwise eligible, leaving states and their safety net hospitals to foot the bill for federally mandated emergency healthcare services. In the limited preliminary injunction order, the court ruled that the Trump Administration’s actions were likely arbitrary and capricious and rulemaking in violation of the Administrative Procedure Act.

Created in 1965, Medicaid is an essential source of health insurance for lower-income individuals and particular underserved population groups, including children, pregnant women, individuals with disabilities, and seniors. The Medicaid program allows each participating state to develop and administer its own unique health plans; states must meet threshold federal statutory criteria, but they can tailor their plans’ eligibility standards and coverage options to residents’ needs. As of January 2025, 78.4 million people were enrolled in Medicaid and the Children’s Health Insurance Program (CHIP) nationwide.  

California’s Medi-Cal program provides healthcare coverage for one out of every three Californians, including more than two million noncitizens. Noncitizens include green card holders, refugees, individuals who hold temporary protected status, Deferred Action for Childhood Arrival recipients, and others. Not all noncitizens are eligible for federally funded Medi-Cal services, and so California uses state-only funds to provide a version of the Medi-Cal program to all eligible state residents, regardless of their immigration status. 

Attorney General Bonta led the attorneys general of Arizona, Colorado, Connecticut, Delaware, Hawaii, Illinois, Massachusetts, Maine, Maryland, Michigan, Minnesota, Nevada, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont, and Washinton in filing the lawsuit.

A copy of the preliminary injunction order is available here.