Huh - would it be possible for a state that cares (say... California?) to check the trucks when entering the state? Or is that not allowed due to the Interstate

Huh - would it be possible for a state that cares (say... California?) to check the trucks when entering the state? Or is that not allowed due to the Interstate Commerce act? Perhaps our CARB exception could allow us to regulate this and change a large fraction of trucks in the country to pollute less...