On July 13, the Tenth Circuit upheld Colorado's renewable energy mandate against a claim that it impermissibly interferes with interstate commerce. This decision, addressing a state's power to encourage or require the development of renewable energy resources and infrastructure, is significant because EPA's Clean Power Planexpected to be finalized within weekscontemplates such policies as one of four "building blocks" for regulating carbon dioxide emissions from power plants. Additionally, the Tenth Circuit's decision may influence the outcome of a challenge to a similar law pending before the Eighth Circuit.
The U.S. Constitution expressly gives Congress the power to "regulate Commerce . . . among the several States." Courts have long interpreted this provision as implying that the states cannot interfere with interstate commerce a doctrine known as the "dormant" or "negative" Commerce Clause. With limited exceptions, a state may not treat out-of-state economic actors differently than in-state ones. The Supreme Court has often explained that the purpose of this...
