The lawsuit argues that Trump overstepped his “lawful authority” in imposing the tariffs. 

“The Constitution assigns to Congress, not the President, the ‘Power To lay and collect Taxes, Duties, Imposts and Excises,’” reads the lawsuit. “Yet over the last three months, the President has imposed, modified, escalated, and suspended tariffs by executive order, memoranda, social media post, and agency decree. These edicts reflect a national trade policy that now hinges on the President’s whims rather than the sound exercise of his lawful authority.”

The states also claimed that by implementing these tariffs, Trump “upended the constitutional order.”

“By claiming the authority to impose immense and ever-changing tariffs on whatever goods entering the United States he chooses, for whatever reason he finds convenient to declare an emergency, the President has upended the constitutional order and brought chaos to the American economy,” the 12 states claimed in the lawsuit.

The lawsuit also claimed that no president has the power to impose tariffs through the International Emergency Economic Powers Act, which is the law that Trump claimed gave him the right to impose the tariffs. 

“The President has no authority to arbitrarily impose tariffs as he has done here,” the plaintiffs stipulate in the lawsuit’s introduction. “The text and history of the International Emergency Economic Powers Act (IEEPA) — the statute the President has invoked for the most damaging of his tariffs — confirm that the President cannot impose such tariffs under that law. And even if it did, it would not allow the worldwide tariffs he has imposed, which were not a response to an emergency as IEEPA defines it and have no nexus to the circumstances that purported to justify them.”  

New York Attorney General Letitia James, representing the state as a plaintiff in the lawsuit, criticized Trump’s tariff policy, claiming that he raised taxes “on a whim.”

“The president does not have the power to raise taxes on a whim, but that’s exactly what President Trump has been doing with these tariffs,” James said.

LIST: THE EXECUTIVE ORDERS, ACTIONS, AND PROCLAMATIONS TRUMP HAS MADE AS PRESIDENT 

Arizona Attorney General Kris Mayes called the president’s tariff policies “reckless” and “illegal.”

“President Trump’s insane tariff scheme is not only economically reckless — it is illegal,” Mayes said. “Arizona cannot afford President Trump’s massive tax increase. No matter what the White House claims, tariffs are a tax that will be passed on to Arizona consumers.”