The Supreme Court's decision in United States v. Morrison represents a continuation of the judicial constriction of Congress' Commerce Clause power that began in United States v. Lopez. Rather than simply distinguishing Lopez and Morrison from its more recent decisions, the Lopez and Morrison Courts revisited interpretive approaches to the Commerce Clause that had lain dormant for more than six decades. This Article first considers Lopez and Morrison in light of the Court's interpretive history with the Commerce Clause. An analysis of this history reveals three dominant interpretive themes, and concludes that the Court's decisions in Lopez and Morrison depart markedly from the interpretive approach taken by the Court since the New Deal. The Article goes on to demonstrate how Morrison in particular signals the resurrection of an interpretive methodology that is more rigidly formalistic and designed to promote more broadly the notion of traditional spheres of state autonomy. Having identified this theoretical shift, the Article discusses the potential implications of this re-emerging, formalistic theory of Commerce Clause jurisprudence for federal civil rights legislation through an analysis of recent constitutional challenges to existing environmental laws.