context: The United States Constitution reserves to the federal government and to Congress in particular the power to regulate commerce among the states. Although the clause speaks explicitly only of the extensive powers given to Congress, it has been interpreted as having a second purpose of preventing individual states from erecting trade barriers and discriminating against out-of-state products and manufacturers or otherwise burdening the flow of interstate commerce.
citation_a.signal: no signal
citation_a.identifier: 519 U.S. 278, 287
citation_a.parenthetical: "The negative or dormant implication of the Commerce Clause prohibits state taxation or regulation that discriminates against or unduly burdens interstate commerce and thereby 'impedfes] free private trade in the national market place.' "
citation_a.sentence: General Motors Corp. v. Tracy, 519 U.S. 278, 287, 117 S.Ct. 811, 136 L.Ed.2d 761 (1997) (“The negative or dormant implication of the Commerce Clause prohibits state taxation or regulation that discriminates against or unduly burdens interstate commerce and thereby ‘impedfes] free private trade in the national market place.’ ”) (internal citations omitted).
citation_b.signal: see also
citation_b.parenthetical: "Time and time again this Court has held that, in all but the narrowest circumstances, state laws violate the Commerce Clause if they mandate 'differential treatment of in-state and out-of-state economic interests, that benefits the former and burdens the latter.' "
citation_b.sentence: See also Granholm v. Heald, — U.S. -, 125 S.Ct. 1885, 1895, 161 L.Ed.2d 796 (2005) (“Time and time again this Court has held that, in all but the narrowest circumstances, state laws violate the Commerce Clause if they mandate ‘differential treatment of in-state and out-of-state economic interests, that benefits the former and burdens the latter.’ ”) (quoting Oregon Waste Systems, Inc. v. Dept. of Environmental Quality of Oregon., 511 U.S. 93, 99, 114 S.Ct. 1345, 128 L.Ed.2d 13 (1994)).