JUSTICE BRENNAN delivered the opinion of the Court:
In 1977, the Minnesota Legislature enacted a statute banning the retail sale of milk in plastic nonreturnable, nonrefillable containers, but permitting such sale in other nonreturnable, nonrefillable containers, such as paperboard milk cartons. 1977 Minn. Laws, ch. 268, Minn. Stat. § 116F.21 (1978). Respondents
The purpose of the Minnesota statute is set out as § 1:
Section 2 of the Act forbids the retail sale of milk and fluid milk products, other than sour cream, cottage cheese, and yogurt, in nonreturnable, nonrefillable rigid or semirigid containers composed at least 50% of plastic.
The Act was introduced with the support of the state Pollution Control Agency, Department of Natural Resources, Department of Agriculture, Consumer Services Division, and Energy Agency,
After the Act was passed, respondents filed suit in Minnesota District Court, seeking to enjoin its enforcement. The court conducted extensive evidentiary hearings into the Act's probable consequences, and found the evidence "in sharp conflict." App. A-25. Nevertheless, finding itself "as fact-finder. . . obliged to weigh and evaluate this evidence," ibid., the court resolved the evidentiary conflicts in favor of respondents, and concluded that the Act "will not succeed in effecting the Legislature's published policy goals . . . ." Id., at A-21. The court further found that, contrary to the statement of purpose in § 1, the "actual basis" for the Act "was to promote the economic interests of certain segments of the local dairy and pulpwood industries at the expense of the economic interests of other segments of the dairy industry and the plastics industry." Id., at A-19. The court therefore declared the Act "null, void, and unenforceable" and enjoined its enforcement, basing the judgment on substantive due process under the Fourteenth Amendment to the United States Constitution and Art. 1, § 7, of the Minnesota Constitution; equal protection under the Fourteenth Amendment; and prohibition of unreasonable burdens on interstate commerce under Art. I, § 8, of the United States Constitution. App. A-23.
The State appealed to the Supreme Court of Minnesota, which affirmed the District Court on the federal equal protection and due process grounds, without reaching the Commerce Clause or state-law issues. 289 N.W.2d 79 (1979). Unlike the District Court, the State Supreme Court found that the purpose of the Act was "to promote the state interests
The parties agree that the standard of review applicable to this case under the Equal Protection Clause is the familiar "rational basis" test. See Vance v. Bradley, 440 U.S. 93, 97 (1979); New Orleans v. Dukes, 427 U.S. 297, 303 (1976).
Respondents apparently have not challenged the theoretical connection between a ban on plastic nonreturnables and the purposes articulated by the legislature; instead, they have argued that there is no empirical connection between the two. They produced impressive supporting evidence at trial to prove that the probable consequences of the ban on plastic nonreturnable milk containers will be to deplete natural resources, exacerbate solid waste disposal problems, and waste energy, because consumers unable to purchase milk in plastic
But States are not required to convince the courts of the correctness of their legislative judgments. Rather, "those challenging the legislative judgment must convince the court that the legislative facts on which the classification is apparently based could not reasonably be conceived to be true by the governmental decisionmaker." Vance v. Bradley, 440 U. S., at 111. See also Day-Brite Lighting, Inc. v. Missouri, 342 U.S. 421, 425 (1952); Henderson Co. v. Thompson, 300 U.S. 258, 264-265 (1937).
Although parties challenging legislation under the Equal Protection Clause may introduce evidence supporting their claim that it is irrational, United States v. Carolene Products Co., 304 U.S. 144, 153-154 (1938),
The District Court candidly admitted that the evidence was "in sharp conflict," App. A-25, but resolved the conflict in favor of respondents and struck down the statute. The Supreme Court of Minnesota, however, did not reverse on the basis of this patent violation of the principles governing rationality analysis under the Equal Protection Clause. Rather, the court analyzed the statute afresh under the Equal Protection Clause, and reached the conclusion that the statute is
The State identifies four reasons why the classification between plastic and nonplastic nonreturnables is rationally related to the articulated statutory purposes. If any one of the four substantiates the State's claim, we must reverse the Minnesota Supreme Court and sustain the Act.
First, the State argues that elimination of the popular plastic milk jug will encourage the use of environmentally superior containers. There is no serious doubt that the plastic containers consume energy resources and require solid waste disposal, nor that refillable bottles and plastic pouches are environmentally superior. Citing evidence that the plastic jug is the most popular, and the gallon paperboard carton the most cumbersome and least well regarded package in the industry, the State argues that the ban on plastic nonreturnables will buy time during which environmentally preferable alternatives may be further developed and promoted.
As Senator Spear argued during the Senate debate:
Accord, id., at 1-2 (statement of Sen. Luther).
We find the State's approach fully supportable under our precedents. This Court has made clear that a legislature need not "strike at all evils at the same time or in the same way," Semler v. Oregon State Board of Dental Examiners, 294 U.S. 608, 610 (1935), and that a legislature "may implement [its] program step by step, . . . adopting regulations that only partially ameliorate a perceived evil and deferring complete elimination of the evil to future regulations." New Orleans v. Dukes, 427 U. S., at 303. See also Katzenbach v. Morgan, 384 U.S. 641, 657 (1966); Williamson v. Lee Optical Co., 348 U.S. 483, 489 (1955); Railway Express Agency, Inc. v. New York, 336 U.S. 106, 110 (1949). The Equal Protection Clause does not deny the State of Minnesota the authority to ban one type of milk container conceded to cause environmental problems, merely because another type, already established in the market, is permitted to continue in use. Whether in fact the Act will promote more environmentally desirable milk packaging is not the question: the Equal Protection Clause is satisfied by our conclusion that the Minnesota Legislature could rationally have decided that its ban on plastic nonreturnable milk jugs might foster greater use of environmentally desirable alternatives.
Second, the State argues that its ban on plastic nonreturnable milk containers will reduce the economic dislocation foreseen from the movement toward greater use of environmentally superior containers. The State notes that plastic nonreturnables have only recently been introduced on a wide scale in Minnesota, and that, at the time the legislature was
See also Transcript of the Full Senate Floor Discussion on H. F. 45, p. 6 (May 20, 1977), reprinted as Plaintiffs' Exhibit J (statement of Sen. Milton); id., at 9 (statement of Sen. Schaaf); id., at 10-11 (statement of Sen. Perpich).
Moreover, the State explains, to ban both the plastic and the paperboard nonreturnable milk container at once would cause an enormous disruption in the milk industry because few dairies are now able to package their products in refillable bottles or plastic pouches. Thus, by banning the plastic container while continuing to permit the paperboard container, the State was able to prevent the industry from becoming reliant on the new container, while avoiding severe economic dislocation.
The Minnesota Supreme Court did not directly address this justification, but we find it supported by our precedents as well. In New Orleans v. Dukes, supra, we upheld a city regulation banning pushcart food vendors, but exempting from the ban two vendors who had operated in the city for over eight years. Nothing that the "city could reasonably decide
Third, the State argues that the Act will help to conserve energy. It points out that plastic milk jugs are made from plastic resin, an oil and natural gas derivative, whereas paperboard milk cartons are primarily composed of pulpwood, which is a renewable resource. This point was stressed by the Act's proponents in the legislature. Senator Luther commented: "We have been through an energy crisis in Minnesota. We know what it is like to go without and what we are looking at here is a total blatant waste of petroleum and natural gas . . . ." Transcript of the Full Senate Floor Discussion on H. F. 45, p. 12 (May 20, 1977), reprinted as Plaintiffs' Exhibit J. Representative Munger said in a similar vein:
The Minnesota Supreme Court may be correct that the Act is not a sensible means of conserving energy. But we reiterate that "it is up to legislatures, not courts, to decide on the wisdom and utility of legislation." Ferguson v. Skrupa, 372 U.S. 726, 729 (1963). Since in view of the evidence before the legislature, the question clearly is "at least debatable," United States v. Carolene Products Co., 304 U. S., at 154, the Minnesota Supreme Court erred in substituting its judgment for that of the legislature.
Fourth, the State argues that the Act will ease the State's solid waste disposal problem. Most solid consumer wastes in Minnesota are disposed of in landfills. A reputable study before the Minnesota Legislature indicated that plastic milk jugs occupy a greater volume in landfills than other nonreturnable milk containers.
The Minnesota Supreme Court found that plastic milk jugs in fact take up less space in landfills and present fewer solid waste disposal problems than do paperboard containers. 289 N. W. 2d, at 82-85. But its ruling on this point must be rejected for the same reason we rejected its ruling concerning energy conservation: it is not the function of the courts to substitute their evaluation of legislative facts for that of the legislature.
We therefore conclude that the ban on plastic nonreturnable milk containers bears a rational relation to the State's objectives, and must be sustained under the Equal Protection Clause.
The District Court also held that the Minnesota statute is unconstitutional under the Commerce Clause
Minnesota's statute does not effect "simple protectionism," but "regulates evenhandedly" by prohibiting all milk retailers from selling their products in plastic, nonreturnable milk containers, without regard to whether the milk, the containers,
Since the statute does not discriminate between interstate and intrastate commerce, the controlling question is whether the incidental burden imposed on interstate commerce by the Minnesota Act is "clearly excessive in relation to the putative local benefits." Pike v. Bruce Church, Inc., supra, at 142. We conclude that it is not.
The burden imposed on interstate commerce by the statute is relatively minor. Milk products may continue to move freely across the Minnesota border, and since most dairies package their products in more than one type of containers,
Pulpwood producers are the only Minnesota industry likely to benefit significantly from the Act at the expense of out-of-state firms. Respondents point out that plastic resin, the raw material used for making plastic nonreturnable milk jugs, is produced entirely by non-Minnesota firms, while pulpwood, used for making paperboard, is a major Minnesota product. Nevertheless, it is clear that respondents exaggerate the degree of burden on out-of-state interests, both because plastics will continue to be used in the production of plastic pouches, plastic returnable bottles, and paperboard itself, and because out-of-state pulpwood producers will presumably absorb some of the business generated by the Act.
Even granting that the out-of-state plastics industry is burdened relatively more heavily than the Minnesota pulpwood industry, we find that this burden is not "clearly excessive" in light of the substantial state interest in promoting conservation of energy and other natural resources and easing solid waste disposal problems, which we have already reviewed in the context of equal protection analysis. See supra, at 465-470. We find these local benefits ample to support Minnesota's decision under the Commerce Clause. Moreover, we find that no approach with "a lesser impact on interstate activities," Pike v. Bruce Church, Inc., supra, at 142, is available. Respondents have suggested several alternative statutory schemes, but these alternatives are either more burdensome on commerce than the Act (as, for example, banning all nonreturnables) or less likely to be effective (as, for example,
In Exxon Corp. v. Governor of Maryland, 437 U.S. 117 (1978), we upheld a Maryland statute barring producers and refiners of petroleum products—all of which were out-of-state businesses—from retailing gasoline in the State. We stressed that the Commerce Clause "protects the interstate market, not particular interstate firms, from prohibitive or burdensome regulations." Id., at 127-128. A nondiscriminatory regulation serving substantial state purposes is not invalid simply because it causes some business to shift from a predominantly out-of-state industry to a predominantly in-state industry. Only if the burden on interstate commerce clearly outweighs the State's legitimate purposes does such a regulation violate the Commerce Clause.
The judgment of the Minnesota Supreme Court is
JUSTICE REHNQUIST took no part in the consideration or decision of this case.
JUSTICE POWELL, concurring in part and dissenting in part.
The Minnesota statute at issue bans the retail sale of milk in plastic nonreturnable, nonrefillable containers, but permits such sale in paperboard milk cartons. Respondents challenged the validity of the statute under both the Equal Protection and Commerce Clauses. The Minnesota District Court agreed with respondents on both grounds. The Supreme Court of Minnesota also agreed that the statute violated the Equal Protection Clause, but found it unnecessary to reach the Commerce Clause issue.
This Court today reverses the Supreme Court of Minnesota, finding no merit in either of the alleged grounds of invalidity. I concur in the view that the statute survives equal protection challenge, and therefore join the judgment of reversal on this
I would not, however, reach the Commerce Clause issue, but would remand it for consideration by the Supreme Court of Minnesota. The District Court expressly found:
At a subsequent point in its opinion, and in even more explicit language, the District Court reiterated its finding that the purpose of the statute related to interstate commerce.
I conclude therefore that this Court has no basis for inferring a rejection of the quite specific factfindings by the trial court. The Court's decision today, holding that Chapter 268 does not violate the Commerce Clause, is flatly contrary
JUSTICE STEVENS, dissenting.
While the Court in this case seems to do nothing more than apply well-established equal protection and Commerce Clause principles to a particular state statute, in reality its reversal of the Minnesota Supreme Court is based upon a newly discovered principle of federal constitutional law. According to this principle, which is applied but not explained by the majority, the Federal Constitution defines not only the relationship between Congress and the federal courts, but also the relationship between state legislatures and state courts. Because I can find no support for this novel constitutional doctrine in either the language of the Federal Constitution or the prior decisions of this Court, I respectfully dissent.
The keystone of the Court's equal protection analysis is its pronouncement that "it is not the function of the courts to substitute their evaluation of legislative facts for that of the legislature." Ante, at 470.
One of the few propositions that this Court has respected with unqualified consistency—until today—is the rule that a federal court is bound to respect the interpretation of state law announced by the highest judicial tribunal in a State.
I find it extraordinary that this federal tribunal feels free to conduct its own de novo review of a state legislative record in search of a rational basis that the highest court of the State has expressly rejected. There is no precedent in this Court's decisions for such federal oversight of a State's lawmaking process.
Once it is recognized that this Court may not review the question of state law presented by the Minnesota courts' decision to re-evaluate the evidence presented to the legislature, the result we must reach in this case is apparent. Because the factual conclusions drawn by the Minnesota courts are clearly supported by the record,
In light of my conclusion that the Minnesota Supreme Court's equal protection decision must be affirmed, I need not address the Commerce Clause question resolved by the majority. Ante, at 470-474. Nonetheless, I believe that the majority's treatment of that question compels two observations.
First, in my opinion the Court errs in undertaking to decide the Commerce Clause question at all. The state trial court addressed the question and found that the statute was designed by the Minnesota Legislature to promote the economic interests of the local dairy and pulpwood industries at the expense of competing economic groups.
Second, the Court's Commerce Clause analysis suffers from the same flaw as its equal protection analysis. The Court rejects the findings of the Minnesota trial court, not because they are clearly erroneous, but because the Court is of the view that the Minnesota courts are not authorized to exercise such a broad power of review over the Minnesota Legislature. See ante, at 471, n. 15. After rejecting the trial court's findings, the Court goes on to find that any burden the Minnesota statute may impose upon interstate commerce is not excessive in light of the substantial state interests furthered by the statute. Ante, at 473. However, the Minnesota Supreme Court expressly found that the statute is not rationally related to the substantial state interests identified by the majority.
The majority properly observes that a state court, when applying the provisions of the Federal Constitution, may not
"Statement of policy. The legislature seeks to encourage both the reduction of the amount and type of material entering the solid waste stream and the reuse and recycling of materials. Solid waste represents discarded materials and energy resources, and it also represents an economic burden to the people of the state. The recycling of solid waste materials is one alternative for the conservation of material and energy resources, but it is also in the public interest to reduce the amount of materials requiring recycling or disposal."
The standard of review under equal protection rationality analysis— without regard to which branch of the state government has made the legislative judgment—is governed by federal constitutional law, and a state court's application of that standard is fully reviewable in this Court on writ of certiorari. 28 U. S. C. § 1257 (3). JUSTICE STEVENS concedes the flaw in his argument when he admits that "a state court's decision invalidating state legislation on federal constitutional grounds may be reversed by this Court if the state court misinterpreted the relevant federal constitutional standard." Post, at 489. And contrary to his argument that today's judgment finds "no precedent in this Court's decisions," post, at 482, we have frequently reversed State Supreme Court decisions invalidating state statutes or local ordinances on the basis of equal protection analysis more stringent than that sanctioned by this Court. E. g., Idaho Dept. of Employment v. Smith, 434 U.S. 100 (1977); Arlington County Board v. Richards, 434 U.S. 5 (1977); Richardson v. Ramirez, 418 U.S. 24 (1974); Lehnhausen v. Lake Shore Auto Parts Co., 410 U.S. 356 (1973). See also North Dakota Pharmacy Board v. Snyder's Drug Stores, Inc., 414 U.S. 156 (1973); Dean v. Gadsen Times Publishing Corp., 412 U.S. 543 (1973); McDaniel v. Barresi, 402 U.S. 39 (1971). Never have we suggested that our review of the judgments in such cases differs in any relevant respect because they were reached by state courts rather than federal courts.
Indeed, JUSTICE STEVENS has changed his own view. Previously he has stated that state-court decisions under the Fourteenth Amendment granting litigants "more protection than the Federal Constitution requires," are in error. Idaho Dept. of Employment v. Smith, supra, at 104 (STEVENS, J., dissenting in part). This is in agreement with the conclusion of one commentator:
"In reviewing state court resolutions of federal constitutional issues, the Supreme Court has not differentiated between those decisions which sustain and those which reject claims of federal constitutional right. In both instances, once having granted review, the Court has simply determined whether the state court's federal constitutional decision is `correct,' meaning, in this context, whether it is the decision that the Supreme Court would independently reach." Sager, Fair Measure: The Legal Status of Underenforced Constitutional Norms, 91 Harv. L. Rev. 1212, 1243 (1978) (footnote omitted).
Thus, JUSTICE STEVENS' argument in the dissenting opinion that today's treatment of the instant case is extraordinary and unprecedented, see post, at 482, and n. 7, is simply wrong.
"23. Despite the purported policy reasons published by the Legislature as bases for enacting Chapter 268, actual bases were to isolate from interstate competition the interests of certain segments of the local dairy and pulpwood industries. The economic welfare of such local interests can be promoted without the remedies prescribed in Chapter 268." App. to Pet. for Cert. A-27 (emphasis added).
In four of the cited cases, the Court reviewed the actions of lower federal, not state, courts. These cases thus shed no light upon the role a state court properly may play in reviewing actions of the state legislature. In Vance v. Bradley and United States v. Carolene Products, Federal District Courts had invalidated federal statutes on federal constitutional grounds. In both cases, this Court reversed because the District Courts had exceeded the scope of their powers by re-evaluating the factual bases for the congressional enactments. See Vance, supra, at 111-112; Carolene Products, supra, at 152, 154. In Ferguson v. Skrupa, a Federal District Court had invalidated a Kansas statute on federal constitutional grounds. This Court reversed, finding that the District Court had exceeded constitutional limitations by substituting its judgment for that of the Kansas Legislature. See 372 U. S., at 729-731. The Court also indicated in Ferguson that its own power to supervise the actions of state legislatures is narrowly circumscribed. Id., at 730-731. Finally, in Henderson Co. v. Thompson, a Federal District Court had sustained a Texas statute in the face of a constitutional challenge. In affirming that decision, the Court simply observed that "[t]he needs of conservation are to be determined by the Legislature." 300 U. S., at 264.
In only one of the cases cited by the majority did the Court review a state-court judgment. In Day-Brite Lighting, Inc. v. Missouri, a Missouri statute was challenged on due process, equal protection, and Contract Clause theories. The Missouri Supreme Court had upheld the statute, and this Court affirmed. In the course of its opinion, the Court stated that it was not free to re-evaluate the legislative judgment or act as "a superlegislature." 342 U. S., at 423, 425. The Court did not comment at all upon the extent of the Missouri Supreme Court's authority to supervise the activities of the Missouri Legislature. Nothing in the Day-Brite Lighting opinion can be construed as the source of the Court's newly found power to determine for the States which lawmaking powers may be allocated to their courts and which to their legislatures.
"The Constitution of the United States in the circumstances here exhibited has no voice upon the subject. The statute challenged as invalid is one adopted by a state. This removes objections that might be worthy of consideration if we were dealing with an act of Congress. How power shall be distributed by a state among its governmental organs is commonly, if not always, a question for the state itself. Nothing in the distribution here attempted supplies the basis for an exception. The statute is not a denial of a republican form of government. Constitution, Art. IV, § 4. Even if it were, the enforcement of that guarantee, according to the settled doctrine, is for Congress, not the courts. Pacific States Telephone Co. v. Oregon, 223 U.S. 118; Davis v. Hildebrant, 241 U.S. 565; Ohio ex rel. Bryant v. Akron Park District, 281 U.S. 74, 79, 80. Cases such as Panama Refining Co. v. Ryan, 293 U.S. 388, and Schechter Poultry Corp. v. United States, 295 U.S. 495, cited by appellants, are quite beside the point. What was in controversy there was the distribution of power between President and Congress, or between Congress and administrative officers or commissions, a controversy affecting the structure of the national government as established by the provisions of the national constitution.
"So far as the objection to delegation is founded on the Constitution of Virginia, it is answered by a decision of the highest court of the state. In Reynolds v. Milk Commission, 163 Va. 957; 179 S. E. 507, the Supreme Court of Appeals passed upon the validity of the statute now in question. . . . A judgment by the highest court of a state as to the meaning and effect of its own constitution is decisive and controlling everywhere." See also Dreyer v. Illinois, 187 U.S. 71, 83-84 (1902); Sweezy v. New Hampshire, 354 U.S. 234, 256-257 (1957) (Frankfurter, J., concurring in result).
"Under the system of government created by our Constitution, it is up to legislatures, not courts, to decide on the wisdom and utility of legislation." 372 U. S., at 729.
The Court went on to explain this constitutional limitation:
"We have returned to the original constitutional proposition that courts do not substitute their social and economic beliefs for the judgment of legislative bodies, who are elected to pass laws. . . . Legislative bodies have broad scope to experiment with economic problems, and this Court does not sit to `subject the State to an intolerable supervision hostile to the basic principles of our Government and wholly beyond the protection which the general clause of the Fourteenth Amendment was intended to secure.'" Id., at 730 (footnote omitted).
The Court's conclusion in Ferguson that the Constitution imposes limitations upon the power of the federal courts to review legislative judgments was clearly correct and was consistent with the structure of the Federal Constitution and "the system of government created" therein. The Constitution defines the relationship among the coordinate branches of the Federal Government and prescribes for each branch certain limited powers. The Federal Constitution, however, is silent with respect to the powers of the coordinate branches of state governments and the relationship among those branches.
In its opinion affirming the trial court's decision, the Minnesota Supreme Court took a similar view of the function to be performed by the Minnesota courts when reviewing Minnesota legislation:
"We are aware of the deference that is accorded to the legislature when the present type of statute is analyzed on equal protection grounds. Nevertheless, our inquiry into the constitutional propriety of the present classification separating paper containers from plastic nonrefillables is dependent upon facts. Based upon the relevant findings of fact by the trial court, supported by the record, and upon our own independent review of documentary sources, we believe the evidence conclusively demonstrates that the discrimination against plastic nonrefillables is not rationally related to the Act's objectives." 289 N.W.2d 79, 82 (1979).
In Idaho Dept. of Employment, the Idaho Supreme Court had invalidated a statutory classification, not because it generally failed to further legitimate state goals, but rather because the court had found that the classification was imperfect since some members of the class denied unemployment benefits were in fact as available for full-time employment as members of the class entitled to benefits under the Idaho statute. See Smith v. Department of Employment, 98 Idaho 43, 43-44, 557 P.2d 637, 637-638 (1976), citing Kerr v. Department of Employment, 97 Idaho 385, 545 P.2d 473 (1976). This Court did not disagree with the Idaho court's finding that the classification was imperfect, but merely held that this imperfection was legally insufficient to invalidate the statute under the Equal Protection Clause. 434 U. S., at 101-102. In Arlington County Board v. Richards, the Virginia Supreme Court had recognized the rational-basis test as the appropriate equal protection standard, but then had proceeded to apply a more stringent standard to the municipal ordinance at issue. The court had expressly noted that the municipal ordinance "may relieve the [parking] problems" to which it was directed. However, the court concluded that the means employed by the county to deal with these problems—a classification based upon residency—created an unconstitutional "invidious discrimination." See Arlington County Board v. Richards, 217 Va. 645, 651, 231 S.E.2d 231, 235 (1977). This Court reversed, rejecting the conclusion that the ordinance's residency classification resulted in an invidious discrimination. 434 U. S., at 7. In Richardson v. Ramirez, a voting rights case, the California Supreme Court was reversed, not because it had re-examined the factual determinations of the California Legislature, but because this Court found that the statutory discrimination at issue was expressly authorized by § 2 of the Fourteenth Amendment. 418 U. S., at 41-56. Finally, in Lake Shore Auto Parts v. Lehnhausen, the Illinois Supreme Court had held, in essence, that a classification used in determining liability for a property tax must, as a constitutional matter, be based upon the nature of the property at issue, and not upon the corporate or noncorporate character of the property's owner See Lake Shore Auto Parts v. Korzen, 49 Ill.2d 137, 149-151, 273 N.E.2d 592, 598-599 (1971). This Court rejected this principle, finding it inconsistent with prior decisions clearly establishing that distinctions between individuals and corporations in tax legislation violated no constitutional rights. 410 U. S., at 359-365.
As the majority observes, the Court in each of these cases reversed the state-court decisions because the state courts had applied an equal protection standard more stringent than that sanctioned by this Court. Quite frankly, in my opinion it would have been sound judicial policy in all four of those cases to allow the state courts to accord even greater protection within their respective jurisdictions than the Federal Constitution commands. See my dissent in Idaho Dept. of Employment, supra, at 104. But what is especially relevant here is the fact that in none of those cases had the state courts found, after a full evidentiary hearing, that the factual predicate for the state law at issue was simply not true. The Minnesota courts in this case made such a finding after the development of an extensive record. The Minnesota courts then applied the correct federal legal standard to the facts revealed by this record and concluded that the statutory classification was not rationally related to a legitimate state purpose. As I read the cases cited by the majority, they are simply inapposite in this case. My own research has uncovered no instance in which the Court has reversed the decision of the highest court of a State, as it does in this case, because the state court exceeded some federal constitutional limitation upon its power to review the factual determinations of the state legislature. The Court has never before, to my knowledge, undertaken to define, as a matter of federal law, the appropriate relationship between a state court and a state legislature.
Moreover, since there is no significant difference between plastic containers and paper containers in terms of environmental impact, and since no one contends that the Minnesota statute will reduce the consumption of dairy products, it is not difficult to understand the state judges' skeptical scrutiny of a legislative ban on the use of one kind of container without imposing any present or future restriction whatsoever on the use of the other.
"12. Despite the purported policy statement published by the Legislature as its basis for enacting Chapter 268, the actual basis was to promote the economic interests of certain segments of the local dairy and pulpwood industries at the expense of the economic interests of other segments of the dairy industry and the plastics industry.
"23. Despite the purported policy reasons published by the Legislature as bases for enacting Chapter 268, actual bases were to isolate from interstate competition the interests of certain segments of the local dairy and pulpwood industries. The economic welfare of such local interests can be promoted without the remedies prescribed in Chapter 268." App. A-19, A-22.
These findings were repeated in the memorandum filed by the trial court in this case:
"The relevant legislative history of Chapter 268 support [sic] a conclusion that the real basis for it was to serve certain economic interests (paper, pulpwood, and some dairies) at the expense of other competing economic groups (plastic and certain dairies) by prohibiting the plastic milk bottle." Id., at A-24.
First, in light of the trial court's factual finding that the Minnesota Legislature enacted the statute for protectionist, rather than environmental, reasons, see n. 12, supra, the Equal Protection Clause and Commerce Clause inquiries are not necessarily as similar as the Court suggests. As the majority acknowledges, if a state law which purports to promote environmental goals is actually protectionist in design, a virtually automatic rule of invalidity, not a balancing-of-interests test, is applied. See ante, at 471. See also New Orleans v. Dukes, 427 U. S., at 304, n. 5.
Second, in Beazer the Court reviewed the decision of a lower federal court, not a state supreme court. While this Court, in its discretion, may elect to deprive lower federal courts of the opportunity to decide particular statutory questions, it seems to me that respect for the Minnesota Supreme Court as the highest court of a sovereign State dictates that we not casually divest it of authority to decide a constitutional question on which it properly declined to comment when this case was first before it. Such deference is especially appropriate here because the Court's analysis of the Commerce Clause issue requires rejection of the state trial court's findings of fact.