Obsolescent Preemption

During the first Trump Administration, cities and states responded to the void in federal climate leadership with a flurry of climate-protective policies and lawsuits. Even during the Biden Administration, subnational actors remained engaged in extensive—and necessary—climate change mitigation strategies. But the specter of preemption looms large over subnational climate action. Scholars of the "new preemption" have documented how conservative state legislatures exercise their preemption power to prevent progressive cities from adopting more protective climate policies. As this Article documents, however, judicial interpretations of preemption can create obstacles for municipalities and states even when they pursue policy agendas that are ideologically consistent with the agendas of their state or federal government.<br><br>The recent fate of two municipal gas bans illustrates this problem. In April 2023, the Ninth Circuit struck down Berkeley, California’s gas ban as preempted under a federal statute concerned with energy efficiency. A similar ban enacted by Brookline, Massachusetts was likewise deemed preempted under state laws related to building safety. Both municipalities had justified their bans as exercises of their police power necessary to protect the health and welfare of their residents. But even though public health regulation has long been viewed as an area of traditional municipal authority, courts struck down the bans under sweeping interpretations of the assertedly preemptive laws. Their swift adoption of expansive theories of preemption raises troubling questions not only for the viability of subnational climate policy, but also about the prospect of success in ongoing subnational climate litigation.<br><br>This Article offers a critique of such unduly expansive applications of preemption grounded in the notion of obsolescence: the idea that a court’s interpretation of supposedly preemptive statutory language can become antiquated over time or be unjustifiably extrapolated to new contexts so as to render a preemption determination inconsistent with the preemptive objective of the legislature. In developing this theory of obsolescent preemption, I explore the theoretical underpinnings of the legislature’s preemption authority and explicate the judicial role in articulating and effecting preemption. After identifying the circumstances in which obsolescence occurs, I describe how obsolescent preemption arose in the gas ban context. Building on this case study, I provide a road map for advocates and courts to use as they think about applying the framework of obsolescent preemption in future litigation. I justify the existence of the theory of obsolescent preemption with respect to theories of federalism, separation of powers, and the twenty-first-century situation of subnational actors vis-a-vis climate change.