A federal court has granted a preliminary injunction preventing the U.S. Department of Homeland Security (DHS) from using Medicaid data from California and other states for immigration enforcement purposes. The decision also blocks the U.S. Department of Health and Human Services (HHS) from sharing Medicaid data with DHS for such purposes until further legal proceedings or a compliant rulemaking process is completed.
California Attorney General Rob Bonta issued a statement following the ruling by the U.S. District Court for the Northern District of California, which found that California and a coalition of states were likely to succeed in their claim that HHS’s actions violated the Administrative Procedure Act’s prohibition on arbitrary and capricious rulemaking.
“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.”
The legal action began on July 1, 2025, when California led a group of states in filing suit against the Trump Administration. The lawsuit argued that transferring Medicaid data to DHS violated federal law and asked the court to halt new transfers or uses of this information for immigration enforcement. According to filings, these actions have contributed to fear among noncitizens, causing some eligible individuals and families to avoid enrolling in emergency Medicaid services, which can increase financial pressure on state safety net hospitals.
Medicaid was established in 1965 as health insurance support primarily aimed at lower-income groups including children, pregnant women, seniors, and people with disabilities. States manage their own versions within federal guidelines; as of January 2025, there were approximately 78.4 million enrollees nationwide under both Medicaid and CHIP programs.
In California specifically, Medi-Cal covers about one-third of residents—including more than two million noncitizens such as green card holders, refugees, those with temporary protected status or Deferred Action for Childhood Arrivals status—and offers state-funded coverage options regardless of immigration status when federal funding does not apply.
Attorney General Bonta led attorneys general from Arizona, Colorado, Connecticut, Delaware, Hawaii, Illinois, Massachusetts, Maine, Maryland, Michigan, Minnesota, Nevada, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont and Washington in bringing forth this lawsuit.
A copy of the preliminary injunction order is available here.
