Think globally, act globally: the limits of local climate policies.

• Author: Wiener, Jonathan B.

This Symposium has focused primarily on recent efforts by several states of the United States to regulate greenhouse gas (GHG) emissions. These state-level efforts include common law liability actions (such as public nuisance lawsuits) brought by several states against large GHG emitters.(1) They also include states' regulation of GHG emissions from mobile sources (such as California's 2002 law restricting carbon dioxide emissions from motor vehicles (2)) and from stationary sources (such as California's Global Warming Act of 2006, (3) an emerging initiative of western states, and the Regional Greenhouse Gas Initiative (RGGI) of seven northeastern states (4)). They include efforts by states to force the federal government to act, such as the lawsuit in Massachusetts v. EPA, (5) recently decided by the U.S. Supreme Court. (6)

The papers in this Symposium make many useful contributions. And the state-level actions reflect creative legal strategies intended to achieve a major environmental objective. In this brief Commentary, I will not seek to recapitulate the papers' insights nor to address each paper individually.

Instead, I will make one basic point: subnational state-level action is not the best way to combat global climate change. This is true even assuming that forestalling global climate change is of utmost importance, (7) and even where the state-level policies are individually well designed. The basic point remains that local action is not well suited to regulating mobile global conduct yielding a global externality. In this Commentary I will argue that subnational state-level action, by itself, is of limited value, and may even yield perverse results; and, given that such state-level action is already occurring, I will suggest what its best uses may be in light of these limitations.

The resort to state-level action is understandable, and perhaps predictable, given the U.S. government's decisions (so far) not to ratify the Kyoto Protocol (8) and not to enact federal legislation regulating GHG emissions. (9) It is nonetheless well understood that these state-level efforts, even those of large states such as California, will have little impact on global emissions and hence little impact on global climate. Moreover, the state-level actions must surmount numerous legal hurdles. Worse, state-level efforts could be not only ineffectual, but counterproductive, increasing net global emissions and undercutting a wider effort to constrain global emissions.

Nevertheless, if well-designed, state-level strategies could yield some significant results, including (i) stimulating technological innovation that could diffuse to other unregulated places; (ii) learning by experimentation with alternative policy designs; and (iii) raising the specter of a patchwork of inconsistent state regulations as a political gambit to motivate industry to support broader federal regulation.

"Think globally, act locally" is good advice for many problems, especially when interpreted not only spatially, but also conceptually as advice to adopt a systems analysis mental framework: consider the complex interconnected whole, and then do what you can to help out in your particular niche while avoiding adverse side effects on other domains. (10) But "think globally, act locally" is not such good advice for protecting global public goods when the externalities arise from widespread and geographically moveable sources, and when local action would have a trivial effect or would merely shift those sources to other locales (potentially causing even greater harm). Because there is no global sovereign to institute global regulation, successful action will require cooperation by the major global actors--a diverse group of powerful national governments who will act only if they perceive their own net benefits to doing so and who are bound to a treaty only if they agree to join. (11) Action by each major national government depends on its confidence that other major countries will also act. The difficult policy challenge of climate change is thus to produce a global public good via the mutual consent of multiple heterogeneous actors. It requires us to "think globally, act globally."

1. LEGAL OBSTACLES TO STATE-LEVEL ACTION

   Before addressing the policy problems with subnational state-level actions to reduce GHG emissions, let me briefly mention the important legal hurdles they must overcome in the U.S. legal system. Common law liability actions (such as public nuisance claims) must pass several tests. They must prove causation, including general causation: do human GHG emissions cause global climate change, and especially the changes that injure the plaintiffs? Plaintiffs must also prove specific causation: did this defendant's GHG emissions cause this plaintiffs harm? (12) Proving causation in court and satisfying the tests for judicial admissibility of scientific expert testimony to prove causation may well be more difficult than persuading legislators or regulators to act based on uncertain model forecasts. Relatedly, the plaintiffs may need to show standing to sue (are their injuries too general? are they redressable?), (13) fend off preemption by the Clean Air Act, establish the elements of negligence, deflect the political question doctrine, (14) and find a remedy for future injuries that the court will be willing to award.

   Meanwhile, state regulation of GHG emissions may face a variety of legal obstacles, including challenges (i) under the Dormant Commerce Clause, especially if states attempt to regulate or tax emissions embedded in products (such as goods, services, and electricity) imported into the state from other states; (ii) under the Dormant Treaty Clause or more generally for interference with the foreign affairs power of the federal government, especially where U.S. states purport to enter into agreements with foreign countries such as Great Britain or the European Union; (15) (iii) under theories of preemption by federal statutes such as the Clean Air Act; and (iv) under the Interstate Compacts Clause, in the cases of RGGI, western states, or other cooperative multistate programs. (16)

   Even if these legal hurdles can be surmounted, there remains a high political hurdle for state-level actions: because GHGs mix globally and have global impacts, local abatement actions pose local costs, yet deliver essentially no local climate benefits. This in turn suggests that local actions will often be difficult to enact. Each state (or country) has an incentive to free ride on other states' (or countries') actions, enjoying the global benefits without bearing the local costs. The result is underinvestment in abatement, unless cooperation can be organized. (17) Indeed, a "race to the bottom" is even more likely in the case of a globally mixing pollutant with no local impacts, because local decisions to relax regulations would reduce costs without incurring the local pollution harms associated with conventional pollutants.

   Yet in fact we do see state-level actions being undertaken in the Northeast and in California, as well as action by the European Union despite U.S. withdrawal from the Kyoto Protocol. Such action may look worthwhile to those who think the costs are low, or favor emissions reductions regardless of the costs, or favor a state patchwork to motivate industry support for a federal (or global) regime, or perceive real costs but favor moving first in order to learn by doing, or perceive real costs but favor action that would impose higher costs on other states or industries (raising rivals' costs), or are governors or other high officials with broader political ambitions. The political coalitions in each state that help secure the enactment of GHG limitations may reflect the combination of ambitious leaders with so-called "Baptists and bootleggers" (18) coalitions--environmentalists seeking to protect the climate, and industry segments (such as alternative energy sources) seeking to raise their rivals' costs. (19)

2. NORMATIVE DISADVANTAGES OF STATE-LEVEL ACTIONS

   But even if these legal and political obstacles can be overcome (and it seems that they are being overcome to some degree, though challenges still await in California and in RGGI), there remains the normative question--whether these state-level actions are desirable.

   No matter where they are emitted, GHGs mix globally in the atmosphere and have global impacts. The benefits of emissions abatement are therefore shared globally. Climate protection is a global public good, and the challenge is to produce this global public good via the consent of heterogeneous national actors. Subnational state-level actions will have a small impact on the global picture, and could even be perverse.

   Each state of the United States--even California--contributes a small share of global GHG emissions. Certainly, no state could effectively control its own ambient level of carbon dioxide or other GHGs, because that ambient level is determined by the worldwide concentration of GHGs in the atmosphere. This shows, incidentally, why regulation of carbon dioxide under the National Ambient Air Quality Standards (NAAQS) and State Implementation Plans (SIPs) of Clean Air Act sections 109 and 110 would likely fail if carbon dioxide were listed as a "pollutant" by the EPA under section 108 of the Clean Air Act. No SIP could, on its own, attain a serious NAAQS for GHGs without international cooperation. The problem is not whether carbon dioxide qualifies as a pollutant, but that state-based ambient standards are a mismatch with a globally mixing GHG. (20) Only international cooperation on emissions limitations can effectively reduce ambient concentrations.

   Even the Kyoto Protocol is not sufficiently global, because it omits emissions limits on the world's largest sources--the United States and China, as well as Australia, India, Brazil, and others. When the Kyoto Protocol was negotiated in 1997...