A coalition of twenty Democratic state attorneys general has filed a lawsuit against the U.S. Department of Transportation (DOT), accusing the agency of leveraging federal highway funds to enforce immigration policies associated with former President Donald Trump.

Federal highway funds are essential financial resources allocated to states for the development and maintenance of critical transportation infrastructure—including roads, bridges, rail systems, airports, and transit stations. Programs like the Highway Trust Fund and the Infrastructure Investment and Jobs Act are designed to enhance road safety and boost local economies.

Controversy erupted after DOT Secretary Sean Duffy sent a letter on April 24 stating that federal transportation funding would be limited to state and local governments that actively cooperate with federal immigration enforcement efforts—such as working with ICE or abandoning “sanctuary” policies.

The attorneys general argue that this condition is illegal and represents an overreach of executive power. According to them, Congress never authorized tying infrastructure funding to immigration enforcement, and doing so would jeopardize critical public works projects, increasing the risk of traffic accidents and fatalities.

Complying with such conditions, they argue, would also force state transportation departments to redirect resources toward immigration enforcement—tasks they are neither trained nor equipped to handle.

Led by the state of California, the lawsuit seeks to halt what plaintiffs describe as a coercive, politically motivated use of essential funds meant to protect public safety and maintain national infrastructure.