Hillel Aron

(CN) — California officials announced on Wednesday that they've filed a lawsuit to block trade tariffs imposed by President Donald Trump.

"It's simple: Trump does not have the authority to impose these tariffs," California Attorney General Rob Bonta said at a press conference. "He must be stopped."

On April 2, Trump announced he was enacting a 10% tariff on all goods being shipped into this country, plus far steeper tariffs on dozens of countries, which he rather confusingly called "reciprocal tariffs." The announcement threatened to unravel the complex web that is the global economy and sent the stock market into a tailspin, and even spooked the bond market. Days later, Trump agreed to pause the steeper tariffs for 90 days, reassuring some but leaving a cloud of uncertainty over the nation's trade regime. And other tariffs are still in place, including the very steep 145% levy on goods imported from China.

Article I, Section 8 of the Constitution gives Congress the sole power to "lay and collect taxes, duties, imposts and excises." But over time, the legislature has ceded some of that power to the president, mostly through signing trade agreements with other countries. To justify his unilateral tariffs, Trump has cited the International Emergency Economic Powers Act of 1977, or IEEPA, which gives the president authority to regulate international commerce during a national emergency. It was, for example, used by President George W. Bush after the 9/11 attacks to block the assets of terrorist groups.

But the word tariffs also never appears in the IEEPA. The state's lawsuit argues that tariffs "are not among the numerous actions that IEEPA authorizes the president to take under a declared emergency... And no president has previously relied on IEEPA to impose tariffs in the half a century since its enactment."

"IEEPA provides no such clear congressional authorization for President Trump’s tariffs, nor the vast expansion of presidential power to tax all goods entering the United States on a whim," the complaint reads.

Bonta appeared at the press conference with Governor Gavin Newsom at an almond farm in Stanislaus County, in the state's central valley, an area where Republicans typically outnumber Democrats. Because any tariff that the U.S. imposes on imports will likely be met with retaliation by other countries, California farmers, who export their food around the world, stand to be devastated by Trump's new trade regime.

"Donald Trump is betraying the people of the Central Valley," Newsom said. "He is betraying the people that supported him. Donald Trump has turned his back on his supporters. We will not turn our back on those that supported Donald Trump. We will have their back."

Newsom called the tariffs "the worst own goal in the history of this country," an apparent reference to a column by the economist Tyler Cohen, and "one of the most self-destructive things that we've experienced in modern American history."

California has filed 15 lawsuits against the Trump administration in the second term alone. Earlier this month, California joined 22 other states in suing the administration to block over $11 billion in cuts to public health care.

"We bring lawsuits when we think we're gonna win," Bonta told reporters. "We've had a lot of success in those lawsuits so far, securing temporary restraining orders and preliminary injunctions... The president can't do unlawful things. It's really that simple. He thinks he can violate the Constitution and the law, and he can't. And so it's up to us to hold him accountable."

California's lawsuit is not the first filed against the federal government over tariffs. On Monday, five small businesses impacted by the tariffs sued Trump in the U.S. Court of International Trade. On Friday, four members of the Blackfeet Nation sued Trump over his tariffs on Canadian imports. And earlier this month, the New Civil Liberties Alliance sued over the tariffs on goods coming in from China.