California's attorney general joined a coalition of 21 state attorneys general and the Pennsylvania governor in challenging a Trump administration health care rule, arguing it would make coverage less affordable and accessible.
The coalition filed an amicus brief with the U.S. Court of Appeals for the Fourth Circuit in City of Columbus v. Kennedy, supporting a federal court ruling that blocked key provisions of the rule issued in June 2025. Attorney General Rob Bonta argued the rule would impose significant compliance costs on states and increase the uninsured population.
According to the brief, the rule would reduce funding for state health insurance exchanges as fewer people enroll in coverage, drive up uncompensated care costs as the uninsured population grows, and impose costs on states beyond those directly affected by the rule.
The U.S. District Court for the District of Maryland blocked the rule's key provisions in June 2026. In a separate victory in August 2026, a federal court in Massachusetts struck down a provision that would have excluded certain types of gender-affirming care from qualifying as essential health benefits under the Affordable Care Act.
The brief was co-led by Bonta and New Jersey Attorney General Jennifer Davenport. Joining them were attorneys general from Arizona, Colorado, Connecticut, Delaware, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Mexico, New York, North Carolina, Oregon, Rhode Island, Vermont, Virginia, and Washington, along with Pennsylvania's governor.