You’d think that any State in the union has substantial latitude in regulating products which are sold there, however in the case of gas mileage restrictions on automobiles it is an unavoidable consequence that because California is such a huge market, its draconian demands on the industry result in the rest of the States being burdened and inconvenienced due to the need of the manufacturers to have assembly lines produce cars which are compliant to California’s ridiculous requirements.
Looks like it might be reasonably prohibited under the Commerce Clause.
Its not just cars, its EVERYTHING...
They declare something has to be some way to sell in that state, industries capitulate so they don’t have to pull out.
Farming/Agriculture etc is another area where this sort of nonsense happens.