federal constitutional authority of state governments to favor local economic interests. The "market participant" exception allows the states to burden interstate commerce-indeed, to discriminate against out-of-state business concerns in an open and overt manner-provided the state itself has "entered the market" by subsidizing private businesses50 or by operating a business as a proprietor.51 The analytic distinction between the state as a "market participant" (i.e., when state activities will not be subject to dormant commerce clause restrictions) and the state as a "market regulator" (i.e., when state activities will be amenable to doctrinal restrictions) is not a bright line, however. Should a state exploit its economic clout to discriminate against commercial transactions occurring beyond its territorial jurisdiction and outside of the particular market in which it is contracting, its behavior may be deemed "downstream regulation" rather than market participation.52 Consistent with the state-protective presumption in the contemporary preemption doctrine, the current doctrine of the dormant commerce clause promises a broad range of state governmental discretion in economic regulation when Congress has not acted to control the field of interstate commerce. Even if the Supreme Court does not totally abandon the balancing approach in dormant commerce clause analysis, its increased deference to state governmental rulemaking in the commercial realm enhances the opportunities for innovative state economic policy under state constitutional and statutory law. In general, a state constitutional grant of economic regulatory powers, or a state constitutional restraint on public and private economic transactions, or any legislative or administrative measure implementing such powers is likely to survive challenge despite its effects on interstate commerce, provided: (1) it is designed to promote traditional police power objectives, such as health or safety, rather than the business interests of its own residents; (2) it treats out-of-state and in-state economic entities evenhandedly; and (3) it does not vary from national standards to such an extent that it imposes conflicting obligations or cumulative burdens on multistate businesses. Takings Clause Doctrine The Fifth and Fourteenth Amendments of the federal Constitution limit the governmental power of eminent domain:53 government may "take" private property, but only for a "public use"; even then, the taking must be accompanied by "just compensation." By conditioning the power of eminent domain on both the demonstration of a public purpose and the government's willingness to pay, the takings clause theoretically promotes several objectives: an expenditure of public monies should secure a public gain, and not merely benefit a politically powerful interest group;54 moreover, a public good should not be extorted from any discrete and identifiable individuals, but financed by the public at large.55 As the Supreme Court has interpreted the takings clause, the legitimacy of a state's exercise of eminent domain can be challenged on four grounds: first, the state has "taken" the property, rather than merely regulated its use by private owners and operators; second, the state cannot establish that the property was taken for a "public use"; third, the state cannot demonstrate that the taking is sufficiently related to the public purpose to be justifiable; fourth, the state has not provided adequate compensation, whether in cash or in kind. As to most of these issues, the takings clause doctrine is both unsettled and opaque.56 Recent developments in the takings clause, which may have particular impact on state land-use regulation, highlight the importance of unraveling its tangled doctrines, however. The first question-whether the state has "taken" or merely "regulated" private property-is crucial, for only in the case of a "taking" is the government required to pay compensation for controlling or burdening the private uses of property. The border between a "taking" and a "regulation" of private property is not marked by any bright and definitive line; nevertheless, it is possible to identify polar positions and characteristic attributes in light of which a state activity can be deemed a "taking" or a "regulation." The classic case of a "taking" is the state's permanent and physical occupation of private property.57 Without regard to the importance of the public interests served, or to the severity of the imposition on the landowner's usual and expected functions, a state's permanent trespass and appropriation of property is virtually certain to be found a “taking.”58 In opposition, the classic case of a "regulation" of private property is the state's prohibition of a noxious use or nuisance.59 Of course, when the state banishes or controls a "harmful" use of private property, it may be favoring an alternative private use to which surrounding property had been or will be committed; traditional police powers have been stretched conceptually to include regulatory zoning that benefits a conforming private use, even when the nonconforming use was not recognized as a public or private nuisance at common law,60 Apart from these polar cases of physical occupation and noxious use, the distinction between a "taking" and a "regulation" has been made on a case-bycase basis,61 with the Supreme Court viewing several variables as relevant. Among them, diminution in the value of property, destruction of investment-backed expectations, and reciprocity of benefits figure prominently in Supreme Court precedents. The more substantial the reduction of the value of the private property, the more likely it is that a "taking" will be found.62 Similarly, the more severe the interference with expectations of a reasonable return on private investment, the more vulnerable a state regulation will be to invalidation for uncompensated losses.63 In contrast, when a state regulatory scheme provides a "reciprocity of advantage" by creating parallel benefits and burdens for all interested parties (for example, in enhancing land value for an alternative activity at the same time that it diminishes land value for the prohibited activity),64 it is less likely to work a compensable "taking." Despite the judiciary's essentially ad hoc, factual inquiries in distinguishing "takings" and "regulations," it is possible to articulate generally the circumstances (apart from the requirements for "public use" and "means-ends fit" to be discussed below) in which a state regulatory scheme may impose uncompensated losses without creating a “taking." The state regulation (1) should not impose a permanent and physical occupation of private property; (2) should not destroy any traditionally recognized attribute of the property rights; (3) should not substantially diminish the commercial value of the property; (4) should not substantially frustrate expectations of a reasonable rate of return on investment; and (5) if at all possible, should secure some reciprocity of advantage for the burdened parties. The second issue in takings clause challengeswhether the state has established a "public use" for the private property-is clearly the least problematic in case doctrine, if only because the Supreme Court has virtually abdicated any serious review of state regulation under this requirement. As early as 1905, the Supreme Court intimated that any use conducive to the public benefit was a "public use" justifying eminent domain, whether or not property was actually devoted to use by the public.65 With the erosion of the distinction between public and private purposes under the takings clause, the "just compensation" requirement has become the surrogate for an independent inquiry into the public purpose of a "taking" of private property.66 In its most recent articulation of the "public use" requirement for eminent domain, the Supreme Court acknowledged that the concept of "public use" is essentially "coterminous with the scope of a sovereign's police powers."67 In contrast, the third issue-whether the state can demonstrate an adequate "means-ends fit” (i.e., whether the statutory scheme is sufficiently related to the alleged public purposes)—lately has been resurrected as a potential obstacle to uncompensated land-use regulations, and may prove to be an independent requirement in the future for exercises of eminent domain even when just compensation is provided. A narrow majority of the Supreme Court re cently required a showing that the particular land-use regulation chosen by the state would closely and substantially further the purposes or objectives for the regulatory scheme.68 This "standard of precision," of course, far exceeds the burden of proof demanded of the state under the "public use" requirement in eminent domain or in review of state economic regulation under the due process clause.69 Whether the justices will maintain their heightened scrutiny of the means-ends fit, of course, remains to be seen. The fourth issue-whether the state has provided "just compensation" for a "taking"-has assumed greater importance since the Supreme Court dramatically changed the constitutional doctrine of "inverse condemnation"70 in 1987. After years of uncertainty over the remedial rights of property owners who establish a regulatory "taking,"71 the Supreme Court has declared that a government must compensate a property owner for whatever "temporary taking" occurs between enactment and invalidation of an offending regulation, at least when the owner is denied "all use" of the property during that period.72 At this point, it is not clear how far-reaching the "temporary takings" doctrine will prove to be. For example, will the damages remedy be limited to temporary denial of all effective use? What substantial time must pass before a "temporary taking" is likely to be found?73 To what damages will the property owner be entitled-consequential damages, loss of good will?74 Ambiguities notwithstanding, it is evident that the "temporary takings" doctrine will be critical for state and local land-use regulators: once the doctrine is extended to zoning cases, government will presumptively be liable for interim damages should land-use restrictions later be deemed compensable "takings."75 Moreover, the doctrine is likely to increase economic incentives for challenges to administrative rulings that inhibit land development.76 Cloudy and uncertain as the takings clause doctrine rightly appears, several of its elements have been revitalized. At the very least, this indicates the potential for a more stringent protection of private property rights under the federal Constitution that constrains a state's economic regulatory powers under its constitutional and statutory law. Such a signal is paralleled, as well, in the Fourteenth Amendment equal protection doctrine. Economic Due Process Fourteenth Amendment constraints on state economic regulation also exist under the due process and equal protection clauses.77 Although earlier in this century the Supreme Court regularly invalidated economic measures under these clauses,78 the Court's decisions since the late 1930s have demonstrated a virtual “hands-off” approach in substantive review of state economic regulation.79 Generally, the Court has enforced a rule of "mere rationality”: a state or local regulation affecting private economic and social interests will not be stricken if there is any "rational relationship" between the regulatory scheme and a legitimate legislative objective, even a "conceivable" purpose that might have motivated the regulating body.80 In a striking departure from rationality review, the Supreme Court lately has examined much more carefully the legitimacy of state regulations that discriminate against the economic interests of out-ofstate enterprises.81 A discriminatory measure enacted only for the purpose of promoting domestic business at the expense of out-of-state trade might not survive the Court's heightened standard of review.82 This development is remarkable for at least two reasons. First, if it leads to an increased judicial solicitude for private economic interests,83 the Court would be abandoning its post-1930s deference to political decisionmaking in areas of socioeconomic policy. Second, unlike its rulings under the dormant commerce clause, judicial enforcement of the equal protection clause would be binding on the Congress as well, restricting its authority under the commerce clause to permit parochial favoritism in state economic regulation.84 However uncertain the future of equal protection restraints on discriminatory economic legislation,85 it is apparent that a state regulation that disfavors out-of-state commercial ventures is vulnerable to attack, even with the approval of Congress, if it only furthers a “naked preference" for domestic industry.86 Authority for State Judicial Declaration Adequate and Independent Unlike the constitutional provisions described above, which restrain all branches of state government in their exercise of police and economic regulatory powers under state constitutions, the doctrines to be examined in this section focus primarily on the federal constitutional authority of the federal judiciary. These doctrines restrain the federal judicial power87 in the interest of full and effective declaration of state law by state courts. Essentially, these doctrines recognize and endorse independent state judicial development of state law, including state constitutional law. Clearly, the independent and adequate state grounds doctrine is the most important among them. This doctrine prevents the U.S. Supreme Court from reviewing a state high court judgment that ultimately rests on a determination of state law, even though the state court may have erroneously decided an issue of federal law.88 When resolution of the state ground does not rely conceptually and doctrinally on the federal law ruling (i.e., “independence" of state ground), and when the state court's judgment would stand even after Supreme Court reversal of its federal law holding (i.e., “adequacy" of state ground), the judgment is immunized totally from appellate review by the Supreme Court.89 At least two objectives justify the Court's selfimposed restraints on appellate jurisdiction under this doctrine. First, the Supreme Court should avoid unnecessary pronouncements on federal constitutional and statutory law, particularly if friction with state substantive policies or state judicial procedural rules might be avoided. Accordingly, the doctrine ensures the necessity for, and the efficacy of, a federal court ruling on appeal that actually resolves a case or controversy.90 Second, the Supreme Court should manifest its respect for the state judiciary's role in developing and applying state law, constitutional and nonconstitutional, substantive and procedural. Thus, the doctrine is a gauge of the strength of "Our Federalism." The Supreme Court has invoked the doctrine in both procedural and substantive contexts. In the procedural context, a state high court typically refuses to decide a federal law issue because the federal rights claimant has failed to comply with a requirement of state court procedure. In such a case, it is clear that the state procedural ground is “independent” of federal law, and the Supreme Court's inquiry addresses the “adequacy" of the procedural rationale to bar consideration of the federal law claim.91 In the substantive context, however, a state high court judgment may appear to rely on both federal and state substantive law, and the Supreme Court's inquiry primarily explores the "independence" of the state law ground:92 did the state court understand state law as the basis for its judgment, or did it refer to state law merely as additional support and illustration of a decision controlled by federal law? Discussion will focus on the substantive applications of the doctrine, for it is in this context that the doctrine has evolved into a viable and powerful instrument of "Our Federalism." For illustration, compare Case 1 and Case 2 in the following example: Case 1: A state high court holds that a state statute violates both state and federal constitutional guarantees. In its consideration of the state law ground, the court finds that the state constitutional standards violated by the statute are different from those under the federal Constitution.93 Case 2: A state high court holds that a state statute violates both state and federal constitutional guarantees. The court reasons that the state and federal provi sions impose identical substantive restraints, and because the state statute violates the federal constitutional standards, it is also invalid under the state constitution.94 The issue of the "independence" of a state law decision generally arises because the state court's opinion has not clarified whether a state law guarantee has a substantive content which is separate and distinct from its counterpart under federal law. It is more likely that the Supreme Court would find such independence in Case 1 than in Case 2: in the latter, the state constitutional law decision appears inextricably enmeshed with, and reliant on, the ruling under federal law. Accordingly, the judgment in Case 1 is more likely to be immunized from Supreme Court review than the judgment in Case 2. In 1983, the Supreme Court refashioned the independent and adequate state grounds doctrine by establishing a standard for review of federal law decisions rendered by state courts.95 The Court will presume that it has appellate jurisdiction over any state high court decision when... a state court decision fairly appears This presumption can be overcome, however, even if a state court chooses to refer to federal law decisions as persuasive (albeit not authoritative) precedents for its state law ruling: [The state court] need only make clear by a plain statement in its judgment or opinion that the federal cases are being used only for the purpose of guidance, and do not themselves compel the result that the court has reached.97 The Court's new standard for resolving the "independence" of state law grounds does balance competing federalism concerns. On the one hand, the approach permits the Supreme Court to maintain the supremacy and uniformity of federal law where a state court decision of a federal claim is both erroneous and determinative of the result in a case; additionally, it informs the state political branches that a potentially erroneous but unreviewable state judicial determination of a federal law issue need not be accorded binding force.98 On the other hand, the approach assures the state judiciary of a firm basis for developing of state constitutional law, by immunizing from review state court decisions based on "bona fide separate, adequate, and independent grounds."99 Given the Court's standard of presumptive review, the burden of demonstrating that a state court judgment "plainly" rests on a state law ruling must be carried by rights claimants in their pleadings, briefing, and argumentation, and by state judges in their legal analysis and opinion writing. How, then, should a claimant's brief or a state judge's opinion be written, what analysis should it provide, to ensure insulation of the state court decision from Supreme Court review? To date, the Court has not proposed or endorsed a set formula guaranteeing nonreviewability, 100 and it would be injudicious, if not misleading, to do so here. Nonetheless, it is possible to suggest a panoply of "analytic devices" which, if used in combination, will more likely than not establish an independent state law ground:101 1) A prefatory discussion of the role of state law in the opinion: in light of the rule that federal constitutional issues should be avoided if the case can be decided on alternative grounds, the claim of right shall be determined first under the state constitution; should the state constitution provide independent support for the claim, there is no need to reach the federal constitutional issues; 2) Explicit acknowledgement of a trend of greater protection for the relevant civil liberty under the state constitutional guarantee than its federal counterpart; 3) Citation to state constitutional law prece- 4) Where federal court precedents are cited, The independent development of state constitutional law may demand analytical ingenuity and creativity, careful attention to writing style, and just "plain hard work."102 This is the price to be paid for the autonomy of the state constitutional enterprise. Abstention and Equitable Restraint Doctrines Whereas the Supreme Court fashioned the independent and adequate state grounds doctrine to limit its own appellate jurisdiction over state high court decisions, the Court has developed a number of rules to restrict the original jurisdiction of the federal district courts, which also operate in favor of state court declaration of state constitutional and statutory law. Known as the abstention and equitable restraint doc trines, these rules generally apply when a federal district court is asked to grant injunctive or declaratory relief to prevent alleged violations of federal constitutional rights by state executive, administrative or judicial officials in their enforcement of state law. 103 In federal court actions against state and local governments, familiarity of governmental counsel with these rules will maximize the opportunities for state court adjudication of state constitutional law issues. Pullman Abstention Doctrine. Where adjudication of an unclear and unsettled question of state law would dispose of a substantial and sensitive federal constitutional question, a federal district court must temporarily abstain from exercising jurisdiction in order to give the state courts an opportunity to decide the state law issue. The rule of Pullman abstention 104 recognizes that federal courts should exercise their equitable powers so as to avoid the "waste" of an unnecessary and tentative decision on federal constitutional grounds, 105 and to accord due respect for state adjudication of ambiguous state law issues. 106 Abstention is conditioned, however, on real uncertainty in the interpretation of a state law; generally, the federal court will not be confident that a bona fide dispute over the meaning or purpose of the state law can be resolved by construing the text or by relying on definitive state court precedents. Even significant ambiguity will not trigger abstention, however, unless clarification of the state law may avoid the need for further consideration of the federal constitutional issue. Notably, the Supreme Court has not yet required abstention in the face of a potential state constitutional challenge, although invalidation of the state law on this basis would clearly moot the federal constitutional question.107 Abstention in Diversity Actions. A federal district court may abstain from exercising diversity jurisdiction to adjudicate an unclear and unsettled issue of state law where there is the potential for federal interference with the operation of state law in a sensitive area of state policy. The Supreme Court has extended the abstention doctrine to federal diversity actions challenging state policies in significant public regulatory fields, such as eminent domain proceedings 108 and management of essential state industries. 109 In these instances, abstention often prevents federal intermeddling in the operation of complex and technical administrative schemes involving difficult questions of state law. 110 Federal district courts are not required to relinquish diversity jurisdiction, however, merely because policies important to the domestic interests of a state are challenged.111 Equitable Restraint Doctrine. A federal district court must refrain from exercising jurisdiction in an equitable action for declaratory judgment or injunctive relief challenging the federal constitutionality of a state law or an official act which is the subject of a pending judicial or administrative proceeding brought by the state against the federal plaintiff. The Supreme Court's current solicitude for "Our Federalism" first congealed in the crucible of the equitable restraint doctrine. 112 The intricate web of rules subsumed under this doctrine113 may promote "comity" between federal and state courts in several ways. By refusing to intervene in state adjudications in order to explore a federal constitutional question, federal district courts do not disrupt the normal processes of the state judiciary, and do not foreclose their opportunities for independent development and enforcement of state substantive law, 114 including state constitutional law. Furthermore, the federal district courts demonstrate confidence in the competence and good faith of the state judiciary to enforce the guarantees of the federal Constitution.115 Whether the equitable restraint doctrine effectively attains its purposes,116 it symbolizes the dedication of contemporary federal constitutional law, in a number of areas, to the maintenance of "Our Federalism." Conclusion This overview of eight federal constitutional doctrines only sketches the outlines of the greater federalist design. At the same time that it restricts state action, American federalism recognizes broad state powers to order public rights and private liberties in economic ventures and political and civil activities. In the efforts of state government to strike a balance among competing public policy objectives, state constitutional law has a central role to play. The potential for state constitutional involvement must be understood and the extent of its authority enforced. Understanding this potential is not, however, an effortless or risk-free task. As the prior discussion should illustrate, successful navigation of federal constitutional restraints requires careful study of the rocks and shoals on which the independent development of state constitutional law might founder. Reliance on any broad-brushed or abstract concept of inherent state sovereignty is unlikely to immunize state action from federal limitations. Only a precise identification of the federal constitutional doctrines implicated by state regulations or judicial rulings, and a detailed analysis of the parameters within which state policymaking may safely operate, will ensure the viability of the state constitutional law enterprise. The warning of Justice Robert Jackson, written for an analysis of "inherent" presidential powers, takes on a different and special meaning in the context of the evolution of state constitutional law: "But I have no illusion that any decision by this Court can |