Although the Constitution’s Commerce Clause is phrased as an affirmative grant of regulatory power,[2] the Supreme Court has long held that the clause has a “negative” aspect that denies States the power to unjustifiably discriminate against or burden the interstate flow of the articles of commerce.[3] The Court has recognized three types of dormant Commerce Clause claims: (1) claims that a state regulation discriminates in favor of state interests or against interstate commerce; (2) claims that a state law regulates extraterritorially; and (3) claims that a state regulation, although not discriminatory or impermissibly extraterritorial, unduly burdens interstate commerce.[4] While its application has varied over time, the general thrust of this judicially-created doctrine is perhaps best summed up as a prohibition on “discriminat[ion] between transactions on the basis of some interstate element.”[5]

Across a series of cases, dormant Commerce Clause challenges to state renewable portfolio standards (RPS) have alleged that RPSs, either through facial operation or practical effect, primarily serve a protectionist function. Generally speaking, these challenges have focused on two arguments. First, that the RPS is designed in such a way as to effectively regulate commerce that takes place entirely outside of the state. And second, that the RPS is structured to capture the local or regional economic benefits of renewable energy development, while shielding local industry from outside competition. The Eighth, Ninth, and Tenth Circuits have each taken up the issue of whether these programs have an improper extraterritorial reach, but their analyses and holdings on the issue seem only to have muddied the waters with inconsistent interpretations of an already convoluted principle.[6] Moreover, the Supreme Court recently rebuffed an industry-lead dormant Commerce Clause challenge to Oregon’s Clean Fuel Program.[7] A victory for the industry petitioners in National Pork Producers Council v. Ross could provide new fodder for attacks on state climate change policies.

But an industry win is far from certain. In recent years, the judiciary has become increasingly skeptical of broad dormant Commerce Clause theories. As the U.S. Court of Appeals for the Ninth Circuit wrote in its opinion in upholding Proposition 12: “While the dormant Commerce Clause is not yet a dead letter, it is moving in that direction.”[8] The doctrine’s most ardent critic, Justice Clarence Thomas, has written in several concurrences and dissents that he believes “that the negative Commerce Clause has no basis in the Constitution.”[9] Moreover, Justice Neil Gorsuch, sitting on the U.S. Court of Appeals for the Tenth Circuit, upheld a Colorado renewable fuels standard against a dormant Commerce Clause challenge.[10] After he joined the Supreme Court, Justice Gorsuch (along with Justice Thomas) voted in favor of a Tennessee law that, according to the majority, “blatantly favors the State’s residents.”[11] Justice Alito, by contrast, has strongly endorsed the Court’s dormant Commerce Clause jurisprudence. As far as we can tell, neither Justice Amy Coney Barrett, nor likely soon-to-be Justice Ketanji Jackson Brown, have opined on the dormant Commerce Clause. Thus, National Pork Producers Council v. Ross may provide a glimpse into their views concerning the doctrine and the extent to which states may regulate by health laws the subjects of legitimate commerce.