Seventeen states and several farm groups have gone to court to stop the Environmental Protection Agency from approving California’s plan to ban gasoline- and diesel-powered cars and trucks.

The Environmental Protection Agency and California on Sept. 15 defended mandating zero-emission vehicles as a routine exercise of federal authority, a claim disputed by red states and farm groups.

No state has ever been granted so much control over an industry that affects other states, Ohio Solicitor General Ben Flowers told the U.S. Court of Appeals for the District of Columbia.

“This is unlike anything you see in the history of our Republic, where we give one state such immense power, particularly in the context of global warming, to regulate something of worldwide significance,” he said.

Ohio and 16 other states are seeking to prevent the EPA from allowing California to phase out gasoline- and diesel-powered vehicles.

If California’s electric vehicle laws hold, other states can adopt the standards. Committed to following California, Washington plans to ban new gas cars and diesel pickups by 2035 and larger new diesel trucks by 2036.

Several farm groups, mostly Midwest producers of crops that yield biofuels, support Ohio and its allied states.

Several car companies, environmental groups and 19 states, including Washington and Oregon, intervened to back California and the EPA.

The red states will suffer as car companies meet sales targets by lowering the price of electric vehicles and then raising the price of conventional vehicles, said Flowers, citing written testimony from economists.

EPA attorney Eric Hostetler said the states’ “theories of monetary injury are overly speculative.” Flowers said car companies haven’t declared they won’t shift costs onto buyers of conventional vehicles.

“If they weren’t cross-subsidizing, they would have every reason in the world to tell you that,” Flowers said.

“One would think they want to assure Ohio farmers who buy pickup trucks they’re not subsidizing electric vehicle purchases by professors in Berkley,” he said.

California has special status to set vehicle-emission standards because its battle against smog predates the federal Clean Air Act. The question is whether that special status can be used to slow climate change.

The EPA’s position has changed with White House administrations. The Biden EPA says the Trump EPA was wrong to prevent California from regulating greenhouse gases from tailpipes.

Jeffrey Wall, an attorney representing farm groups and fuel companies, said such a huge question should be answered by Congress, not the EPA.

“EPA is claiming the authority to let California be a climate-change regulator and drive electrification of the nation’s vehicles,” he said. “This is not, ‘We need our own standards because of smog in L.A.’”

Wall likened the case to Supreme Court rulings barring EPA from regulating greenhouse gases from power plants and the Biden administration from forgiving student loans. The majority ruled in both cases that the executive branch took action without strong congressional direction.

“The question is: Can EPA let a state be a climate-change regulator?” Wall said. “If it’s a major question, it’s pretty easy to resolve the case.”

A three-judge panel heard the arguments: Judges Robert Wilkins, Michelle Childs and Bradley Garcia.

Wall said the EPA can’t justify the need for California’s vehicle-emission standards. They won’t change global temperatures, he said.

Wilkins, a native of Indiana, questioned that reasoning. “Those of us from the country have a saying,” he said. “When you’re in a hole, the first rule of holes is stop digging.”