Back in 2007, the Intergovernmental Panel on Climate Change (IPCC) noted the likelihood of an increase in what is now often referred to as "climate change" or "climate justice" litigation. The reason for the increase, according to the IPCC, is that "countries and citizens [will] become dissatisfied with the pace of international and national decision-making on climate change." Just over a decade later, that observation now looks quite prescient, with several cities and counties taking the oil industry to court over climate-related damages.
In addition to suits against national governments based on international and national environmental laws in various countries, the IPCC pointed to the first climate change tort case brought in the United States: American Electric Power Co. v. Connecticut (AEP). In that case, states sued major oil and gas companies for climate change harms caused by their greenhouse gas emissions based on the common law action of public nuisance. The case was eventually dismissed on the grounds that the Clean Air Act vests the power to regulate such emissions in the EPA, and thus courts did not have authority to address the issue through federal common law. The defeat forced advocates to rethink their legal strategies, but it hasn't deterred them from pressing their case in court.
Indeed, some of the newer cases appear to have a greater chance of success than AEP, in part because of those different approaches. But two other things have changed, as well. First: the evidence is strong and getting stronger. We know a lot more about the causal links between climate change and the greenhouse gas emissions from the fossil fuel industry, and between climate change and myriad risks to life on this planet, such as sea-level rise, droughts, wildfires, and hurricanes. Second, we also know a lot more about the fossil fuel industry's continued marketing of its products notwithstanding its decades-long knowledge of these links.
Among the promising recent cases are those filed last year by several California counties and cities. The localities sued Chevron, ExxonMobil, Shell, and other major fossil fuel producers for current and future damage to homes and infrastructure caused by climate change-induced sea-level rise. Importantly, the plaintiffs filed in state court because they brought only state common law claims, rather than a federal common law claim such as that in AEP. While the U.S. Supreme Court's ruling in AEP concluded that the states' federal common law claim of public nuisance was "displaced" by the Clean Air Act, the Court left open the possibility that the plaintiffs could bring state claims for climate harms.
Although longstanding, federal common law such as the public nuisance claim in AEP is much more limited than state common law, both in types of claims and the frequency with which they are brought. Federal common law cases are relatively rare because state common law is usually more appropriate for the types of harms experienced by individuals and municipalities; only in exceptional cases involving interstate pollution has the Court required a federal law of decision to ensure uniformity.
In all the California cases, the fossil fuel industry argued that climate change issues made the cases exceptional, requiring resolution under federal law. Thus, they argued, the state claims were preempted by federal common law and belonged in federal court. The cases were consolidated into two; one federal district judge agreed that ...