## Facts

- Several States, the City of New York, and three land-trust organizations sued six large electric power companies operating fossil-fuel-fired power plants in multiple States.
- Plaintiffs alleged defendants were major U.S. carbon dioxide emitters and that their emissions contributed to global warming and related harms (e.g., sea-level rise, extreme weather, damage to public resources, infrastructure, and land-trust properties).
- Plaintiffs asserted claims under federal common-law public nuisance (and alternatively under state nuisance law).
- Plaintiffs sought injunctive relief requiring defendants to cap carbon dioxide emissions at then-current levels and reduce emissions annually for at least a decade.
- The district court dismissed the actions as presenting a nonjusticiable political question, and plaintiffs appealed.

## Issues

1. Whether claims seeking abatement of greenhouse-gas emissions under federal common-law public nuisance present a nonjusticiable political question.
2. Whether the States, the City of New York, and the land trusts adequately alleged Article III standing (injury, causation, and redressability).
3. Whether federal common law recognizes an interstate public nuisance claim for greenhouse-gas emissions contributing to climate change.
4. Whether federal statutory law, principally the Clean Air Act, displaced any applicable federal common-law nuisance cause of action as of the time of decision.
5. Whether the complaints plausibly stated a claim for public nuisance at the pleading stage.

## Decision

- The Second Circuit vacated the dismissal and remanded.
- The court held the claims were justiciable and not barred by the political question doctrine.
- The court held plaintiffs adequately alleged Article III standing at the pleading stage.
- The court held federal common law of interstate public nuisance could apply to greenhouse-gas emissions contributing to global warming.
- The court held federal common law was not displaced at that time because no federal regulatory scheme then directly governed the specific carbon dioxide emissions from defendants’ power plants.

## Legal Principles

- A case is not a political question merely because it has policy implications; courts may adjudicate interstate pollution disputes using established nuisance doctrines where judicially manageable standards exist.
- States may receive “special solicitude” in the standing analysis in suits addressing climate-related harms to sovereign and quasi-sovereign interests.
- Causation and redressability can be satisfied at the pleading stage in multi-source pollution cases where defendants are alleged to make a meaningful contribution to the harm and requested relief would at least lessen or slow the injury.
- Federal common law governs certain interstate pollution disputes, including claims framed as unreasonable interference with public rights affecting multiple States.
- Federal common law is displaced when Congress, through statute and authorized agency action, occupies the field or provides a comprehensive regulatory scheme addressing the emissions at issue; absent such regulation as applied to the relevant sources and pollutants, displacement is not established.

## Conclusion

The Second Circuit held that States, a municipality, and land trusts could pursue federal common-law public nuisance claims seeking injunctive limits on major power companies’ carbon dioxide emissions because the claims were justiciable, standing was adequately alleged, federal interstate nuisance doctrine applied, and the Clean Air Act had not yet displaced the federal common-law remedy on the record before the court.


Connecticut v. Am. Elec. Power Co., 582 F.3d 309 (2d Cir. 2009)