APPEAL FROM THE UNITED STATES DISTRICT COURT FOR THE SOUTHERN DISTRICT OF MISSISSIPPI
MR. JUSTICE BRENNAN delivered the opinion of the Court.
Section 11 of Mississippe's Regulation Governing the Production and Sale of Milk and Milk Products in Mississippi, promulgated by the Mississippi State Board of Health (1967), provides, among other things, that "[m]ilk and milk products from... [another State] may be sold in... Mississippi... provided... that the regulatory agency [of the other State that] has jurisdiction accepts Grade A milk and milk products produced and processed in Mississippi on a reciprocal basis."*fn1
The question presented by this case is whether Mississippi, consistently with the Commerce Clause, Art. I, § 8, cl. 3, of the Constitution,*fn2 may, pursuant to this regulation, constitutionally deny a Louisiana milk producer the right to sell in Mississippi milk satisfying Mississippi's health standards solely because the State of Louisiana has not signed a reciprocity agreement with the State of Mississippi as required by the regulation. A three-judge District Court in the Southern District of Mississippi rejected appellant's Commerce Clause challenge, holding that "[s]section 11 is within the permissible limits of state police powers even though it incidentally or indirectly involves or burdens interstate commerce." 383 F. Supp. 569, 575 (1974). We noted probable jurisdiction of appellant's appeal, 421 U.S. 961 (1975). We reverse.*fn3
Appellant, The Great Atlantic & Pacific Tea Co., Inc. (A&P), Maryland corporation, owns and operates 38 outlets in Mississippi that engage in the retail sale
of milk and milk products. A&P also operates at Kentwood, La., a plant for the processing of raw milk into milk and milk products for delivery to its retail outlets. A&P invested over $1 million in the Kentwood processing facilities, intending that part of the dairy products produced at the facility would supply its retail outlets in Mississippi. However, A&P's application on August 28, 1972, to the Mississippi State Board of Health for a permit to distribute the products from its Kentwood facility for sale in Mississippi was denied by the Board because A&P failed to submit the reciprocal agreement between Louisiana and Mississippi required by § 11.*fn4 Appellant thereupon brought this action.
Evidence was stipulated before the District Court which conclusively established that the milk produced at the Kentwood plant fully complied with the requirements of § 11 in all respects save the required reciprocity agreement. The Kentwood plant had received milk sanitation-compliance ratings in excess of 90% in all respects following each inspection by Louisiana officials. These sanitation-compliance ratings were published in the Sanitation Compliance and Enforcement Ratings of Interstate Milk Shippers, a list compiled by the Public Health Service and the Food and Drug Administration of the United States Department of Health, Education, and Welfare (HEW), which includes only processors receiving compliance ratings from state officials who have been certified by the Public Health
Service. Further, the parties stipulated that the Supervisor of the Milk Control Program of the Mississippi State Board of Health testified, on the basis of an inspection by Louisiana officials of the Kentwood plant reported on an HEW form, that Kentwood milk would be acceptable in Mississippi as the Louisiana regulations were substantially equivalent to Mississippi's within the meaning of § 11. Thus only the lack of a reciprocity agreement between the two States prevented appellant from marketing its Kentwood milk at its Mississippi retail outlets.*fn5
Mississippi's answer to appellant's Commerce Clause challenge is that the reciprocity requirement of § 11 is a reasonable exercise of its police power over local affairs, designed to assure the distribution of healthful milk products to the people of its State. We begin our analysis by again emphasizing that "[t]he very purpose of the Commerce Clause was to create an area of free trade among the several States." McLeod v. J. E. Dilworth Co., 322 U.S. 327, 330 (1944). And at least since Cooley v. Board of Wardens, 12 How. 299 (1852), it has been clear that "the Commerce Clause was not merely an authorization to Congress to enact laws for ...