Page:NPPC v. Ross.pdf/4

4 the Court does not mean to trivialize the role territory and sovereign boundaries play in the federal system; the Constitution takes great care to provide rules for fixing and changing state borders. Art. IV, §3, cl. 1. Courts must sometimes referee disputes about where one State’s authority ends and another’s begins—both inside and outside the commercial context. Indeed, the antidiscrimination principle found in the Court’s dormant Commerce Clause cases may well represent one more effort to mediate competing claims of sovereign authority under our horizontal separation of powers. But none of this means, as petitioners suppose, that any question about the ability of a State to project its power extraterritorially must yield to an “almost per se” rule under the dormant Commerce Clause. This Court has never before claimed so much “ground for judicial supremacy under the banner of the dormant Commerce Clause.” United Haulers Assn., Inc. v. Oneida-Herkimer Solid Waste Management Authority, 550 U. S. 330, 346–347. Pp 8–14.

Petitioners overstate the extent to which Pike and its progeny depart from the antidiscrimination rule that lies at the core of the Court’s dormant Commerce Clause jurisprudence. As this Court has previously explained, “no clear line” separates the Pike line of cases from core antidiscrimination precedents. General Motors Corp. v. Tracy, 519 U. S. 278, 298, n. 12. If some cases focus on whether a state law discriminates on its face, the Pike line serves as an important reminder that a law’s practical effects may also disclose the presence of a discriminatory purpose. Pike itself concerned an Arizona order requiring cantaloupes grown in state to be processed and packed in state. 397 U. S., at 138–140. The Court held that Arizona’s order violated the dormant Commerce Clause, stressing that even if that order could be fairly characterized as facially neutral, it “requir[ed] business operations to be performed in [state] that could more efficiently be performed elsewhere.” Id., at 145. The “practical effect[s]” of the order in operation thus revealed a discriminatory purpose—an effort to insulate in-state processing and packaging businesses from out-of-state competition. Id., at 140. While this Court has left the “courtroom door open” to challenges premised on “even nondiscriminatory burdens,” Davis, 553 U. S., at 353, and while “a small number of our cases have invalidated state laws … that appear to have been genuinely nondiscriminatory,”