Chasing the Wind: Regulating Air Pollution in the Common Law State

Introduction
THE CLEAN AIR ACT of 1970 (CAA) is broadly understood as a pivotal moment in the history of U.S. environmental policy, entailing a radical shift away from an earlier common law regime that was operated piecemeal by local and state governments. The CAA superceded these decentralized approaches with federal, uniform, and proactive law. But most importantly, it is thought to embody a shift in priorities away from an earlier deference to industrial concerns toward a new and uncompromising commitment to the protection of public health.
The act's absolutist reputation rests primarily on the ambitiousness of the promise it encodes in a central provision mandating the promulgation of primary ambient air-quality standards.1 In setting these standards, the act requires the EPA to establish maximum permitted levels of regulated pollutants no higher than what the protection of public health against pollution-induced disease demands. These standards exemplify a broader category of regulatory interventions based on scientific assessment of hazards from pollution exposure, frequently termed "risk-based" or "health-based" standards. In addition, the CAA employs a secondary regulatory framework that sets standards based on the feasibility of pollution mitigation, termed "technology standards." Whereas technology standards are inherently based on feasibility and cost, these considerations may not be taken into account in setting risk standards.
Terms for technology standards include "Best Available Technology" (BAT), "Best Practicable Means" (BPM), "Maximum Achievable Control Technology" (MACT), and many others. All of these approaches employ the similar core logic of setting standards with reference to the pollution reduction capabilities of specific technological means. The standards can take the form of a requirement to install particular pollution-control devices or employ other mitigation measures (prescriptive standards). More commonly, however, these standards impose a percentage reduction in emission that is known to be achievable through technological measures of demonstrated feasibility (performance standards).2 In the latter case, sources are free to employ alternative means, as long as they afford pollution reduction at least equal to the level of effectiveness that can be achieved by the technology serving as the basis for the standard.
I argue that technology and risk standards represent the current incarnation of alternative responses to the regulatory dilemma posed by air pollution since the beginning of industrialization. By the mid-nineteenth century, the forerunners of the two current regulatory approaches had become institutionalized. In Germany, standard-setting was guided by technological feasibility and was implemented through proactive licensing processes conducted by administrative agencies within a civil law framework. Under English common law, the organizing principle of air pollution regulation was the amelioration of proven harms within a reactive system that depended upon judicial resolution of nuisance disputes. By contrast to the German approach, English common law in principle imposed an absolute duty to eliminate injury from pollution ("absolute liability" in legal parlance). As such, technology and risk standards are planted in the different legal traditions of the civil law and the common law respectively.
In place of the predominant risk-based standards within the CAA, technology standards are the European instrument of choice.3 This book argues that the continuity between risk standards and nuisance law, or conversely, the incompatibility of technology standards with common law principles, is key to the divergent evolution of the European and American regimes. Differences in styles of implementation follow from the two regimes' core standard-setting rationales, as well. American air pollution regulation accords a much greater role to scientific proof of harm, quantitative risk assessment, and frequent judicial oversight than do the corresponding European processes.
The limited inroads made by technology standards into the U.S. air quality regime have drawn sharp political and scholarly criticism on two grounds: their purported economic inefficiency,4 and a more profound challenge that they pose to the democratic legitimacy of these standards.5 The resonance of this latter normative charge in American political discourse is perhaps best reflected in the frequent substitution of the term "command and control"--a term with distinct military, and even authoritarian connotations--for the more neutral "technology standards."6