The suit, filed in the U.S. District Court for the District of Massachusetts, challenges a March 31 executive order that the coalition says attempts to establish a national list of eligible voters and directs the U.S. Postal Service to transmit mail ballots only to those on the list, the Connecticut AG's office said.

"The Constitution plainly forbids the President from commandeering elections to manipulate and micromanage how we vote," Tong said in the release. "This executive order is an illegal attempt to disenfranchise millions of voters and fundamentally alter how Americans vote."

According to the press release, the order threatens states and election officials with criminal prosecution and the loss of federal funding if they do not comply. The coalition argues that the order would require states to act contrary to their own voter roll procedures, vote-by-mail systems, and voter registration laws.

The attorneys general allege in the complaint that the U.S. Constitution gives states the primary authority to administer elections and does not allow the President to unilaterally impose changes to federal election procedures "without an act of Congress permitting him to do so," the release states.

The coalition further argues that the order would force states to "upend their existing election administration procedures" within weeks of primary elections and months before mail voting begins for the 2026 general election, which it says "will undoubtedly create confusion, chaos, and distrust in state election systems."

The plaintiffs allege the order violates the separation of powers and unlawfully interferes with state mail voting programs. They ask the court to prevent the federal government from implementing or enforcing the executive order.

The suit is led by the attorneys general of Massachusetts, California, Nevada, and Washington. Joining them are the attorneys general of Arizona, Colorado, Connecticut, Delaware, the District of Columbia, Illinois, Maine, Maryland, Michigan, Minnesota, New Jersey, New Mexico, New York, North Carolina, Oregon, Rhode Island, Vermont, Virginia, and Wisconsin, along with the Governor of Pennsylvania.

"We are coordinating closely with states across the country and we are suing to protect our democracy," Tong said.