Trucking and Towing Cases Illuminate Preemption Trends in the Supreme Court

A central theme of environmental law is the division of regulatory authority between states and the federal government. Federal environmental statutes envision an active role for states in implementing and assuring compliance with national standards. Under the Clean Air Act, a quintessential example of cooperative federalism, states are responsible for developing implementation plans to ensure that air quality meets National Ambient Air Quality Standards, which are established by the federal government. 42 U.S.C. §§ 7409, 7410.