The Justice Department has sued four Democratic-led states over their refusal to provide confidential license plates to federal agents, escalating the Trump administration’s legal campaign against state policies that restrict cooperation with federal civil immigration enforcement.

The separate lawsuits target Maine, Massachusetts, Oregon and Washington, all of which DOJ says have denied or paused access to undercover license plates for federal law enforcement agencies, including components of the Department of Homeland Security such as U.S. Immigration and Customs Enforcement and Customs and Border Protection. The suits were filed Wednesday in federal district courts in the affected states and announced Thursday by the Justice Department.

At the center of the cases is a narrow but operationally important law enforcement tool: confidential or undercover license plates that do not identify a vehicle as belonging to a government agency. Federal officials say those plates are needed to protect agents, preserve surveillance operations and prevent targets from tracking or evading federal officers. State officials say their restrictions are aimed at civil immigration enforcement, not criminal law enforcement, and reflect concerns about the use of unmarked vehicles in arrests by agents who may not be readily identifiable to the public.

The Justice Department framed the four policies as unconstitutional discrimination against the federal government. In its announcement, DOJ said the states are “denying confidential license plates to federal agents” after refusing to rescind their policies in response to a department letter. Acting Attorney General Todd Blanche said the states were denying plates to DHS components, including ICE, while issuing them to their own state agencies, calling the approach “discriminatory and obstructionist.”

The lawsuits argue that the state policies violate the Supremacy Clause and the related doctrine of intergovernmental immunity, which generally prevents states from regulating or discriminating against the federal government’s lawful operations. DOJ says the federal government, not the states, has constitutional authority over immigration and border enforcement, and that motor vehicle agencies cannot condition access to a law enforcement tool on whether a federal vehicle might be used in civil immigration work.

State officials are preparing to defend the policies. Maine Secretary of State Shenna Bellows, who oversees the state’s plate program, said Maine’s position would stand up in court and sharply criticized ICE’s conduct in the state. Maine Attorney General Aaron Frey had already disputed DOJ’s contention that the policy obstructs federal enforcement, arguing in correspondence that the program reflects a legitimate decision not to allow state resources to be used for civil immigration operations that state officials view as abusive or unconstitutional.

Washington Gov. Bob Ferguson said his state continues to assist federal criminal law enforcement but will not facilitate civil immigration tactics it considers unlawful. In comments reported by The Associated Press, Ferguson said judges around the country have found that DHS tactics in civil immigration enforcement often violate constitutional protections, and he said Washington would not help facilitate that conduct.

Massachusetts officials also signaled resistance. The lawsuit filed in Boston names Gov. Maura Healey, Attorney General Andrea Campbell and state transportation officials, according to Axios Boston. The administration is asking a federal judge to make the state Registry of Motor Vehicles issue confidential plates to federal agents carrying out civil immigration arrests. Healey defended the denial, saying the state supports legitimate law enforcement work but would not help ICE “operate in secret” while taking people off the streets.

Oregon’s case has a slightly different posture because state officials have described the current policy as a temporary pause while the Department of Motor Vehicles reviews the undercover vehicle registration program. Oregon Public Broadcasting reported that the Oregon DMV paused disbursing new undercover plates to all federal agencies beginning April 15. Oregon officials said state and local law enforcement were not affected and federal agencies already in the program could continue using existing unexpired plates.

DOJ says that distinction does not cure the alleged constitutional problem. In the Oregon and Washington litigation, federal lawyers said Oregon’s DMV policy “illegally discriminates against the United States” and violates the Supremacy Clause. The complaint argues that federal law enforcement agencies should not be subject to state DMV policies that, in DOJ’s view, disregard officer safety, public safety and federal operational needs.

The practical dispute reflects the broader political and legal fight over President Donald Trump’s immigration agenda. Since returning to office, Trump has pushed a more aggressive deportation program, while Democratic governors, attorneys general and city officials have tried to limit state and local participation in civil immigration enforcement. Those efforts have included sensitive-location guidance, sanctuary-style limits on cooperation, debates over officer identification and challenges to the use of masks or unmarked vehicles by federal agents.

The administration’s legal theory fits a wider Justice Department strategy. DOJ said Blanche has directed the Civil Division to identify state and local laws, policies and practices that facilitate violations of federal law or impede lawful federal operations. The plate lawsuits follow that directive and could become a test case for whether federal courts view state motor vehicle policies as neutral administration of state property or impermissible regulation of federal enforcement.

The states are likely to argue that they are not blocking federal agents from operating, making arrests or driving on state roads. Their position is that states can decide how to administer confidential plate programs, especially when the requested use involves civil immigration enforcement rather than ordinary criminal investigations. Oregon officials, for example, have said the review does not prevent federal vehicles from legally operating in the state.

For federal agencies, however, the difference between a confidential plate and a visibly federal vehicle can be central to field operations. DOJ says identifiable vehicles can expose agents to harassment, compromise investigations and allow targets to evade law enforcement. The department has emphasized cases involving violent criminals, gang members, cartel associates, sex offenders and human traffickers, though the state policies at issue focus heavily on civil immigration work rather than criminal prosecutions.

The lawsuits do not immediately resolve whether the states must issue the plates. Federal judges in each district will first consider DOJ’s requests for relief and the states’ defenses. Because the suits were filed separately, rulings could develop at different speeds and potentially produce different outcomes, increasing the chance that appellate courts will be asked to clarify how the Supremacy Clause applies to state-run confidential plate programs.

For now, the litigation gives both sides a concrete vehicle for a larger argument. The Trump administration says Democratic-led states are obstructing lawful federal enforcement and putting officers at risk. The states say they are protecting residents, civil liberties and public accountability by refusing to lend state systems to secretive civil immigration operations. The courts will decide whether those state choices are permissible oversight or unconstitutional interference with federal power.