The model of cooperative federalism, which engages both the federal and state governments in setting and meeting environmental goals, has dominated the environmental regulatory field since the 1970s. It integrates national policies and interstate environmental pollution reduction goals with the sensibilities and flexibility of locally tailored actions. Recent trends in federalism jurisprudence, however, have circumscribed both federal and state power to regulate in the environmental arena. Courts' applications of federalism principles to constrict both federal and state solutions can impede the stronger environmental protection that the public is increasingly demanding.
At the same time, Congress and the executive branch have failed to advance key public environmental goals. For example, the federal government has failed both to address global climate change threats and to move aggressively forward on clean energy development solutions. Federal actions to reduce mercury pollution from coal plants and various pollutants from cars and trucks have widely been criticized as too little, too late. The political will for environmental leadership at the federal level has stagnated in the early part of the twenty-first century.
The states are serving as Justice Brandeis's fifty laboratories of democracy.1 They are stepping up to fill this environmental law and policy gap as federal actions have been viewed as insufficient or, in some cases, counterproductive.
For example, more than a dozen states have enacted new statutes or regulatory standards directed at reducing more mercury pollution from coal plants and sooner than the federal standards require.2 Twenty-eight states and the District of Columbia have enacted renewable energy standards requiring utilities to provide an increasing percentage of the power supplied to consumers from wind power, solar energy, and other relatively cleaner "alternative" energy sources.3 Sixteen states are following California in adopting "clean car" standards, designed to reduce carbon dioxide pollution from cars over the next decade,4 and close to twenty states are enacting various forms of legislation, regulations, and executive actions designed to reduce greenhouse gas pollution in order to help solve climate change problems.5
While state governments are exerting greater responsibility for environmental protection in these and other related ways, the federal courts have sometimes applied the Supremacy Clause, federal preemption principles, and dormant commerce clause principles to strike down state laws that are held to conflict with federal law6 or place an undue burden on interstate commerce.7
The balance of federal and state power in the environmental context is being disrupted. State environmental policies can and should be more than merely stronger stop-gap measures. Often these policies are carefully designed and tailored to meet the goals, needs, values, and circumstances of each state. Furthermore, state policies can create significant environmental benefits and experience, particularly when, as now, a large number of states step up to act, producing both cumulative impacts and comparative experiences.
A key question moving forward is how best to preserve the most significant benefits of these state policies over the long term. How and when should the courts and Congress create space for states to act more strongly in the interests of the environment and of their citizens? Moreover, if and when Congress does eventually act on these pressing environmental issues, such as global climate change solutions, how can new federal legislation ensure the integrity of a national regulatory scheme while retaining the strongest elements of existing state measures? Should it matter how many states have stepped up to act when the federal government has not?
This Article focuses on one key point for consideration. When there is an emerging consensus of state legislative actions moving in the same general direction in a particular environmental field, should that influence a reviewing court's application of federal preemption principles? …