FactoryIf Congress and the president fail to tackle global warming, can courts step in? Can federal judges allow people struggling with the losses of global warming to sue polluters directly?

The idea may at first seem crazy. In a legal world obsessed with claims of judicial activism, the image of a judge taking on a global problem like climate change seems like the punch line to a bad joke at an Exxon board meeting. But it turns out there is a long and proud history of judges addressing pollution in the absence of environmental regulation. For much of the last century — long before Congress acted — federal courts allowed plaintiffs to seek injunctions to stop all kinds of pollution. Successful suits prevented an ore smelter from releasing deadly atmospheric arsenic over the homes and families of Utah, the City of Chicago from draining its sewage into St. Louis’ drinking supply, and New York City from dumping its garbage into the Atlantic, where it washed up on the beaches of the New Jersey Shore. Today, states and environmentalists are turning to these and other historic precedents to make the case that climate change, too, belongs in the courts — when the other branches of government refuse to act.

The Climate DeskThe current battle began in 2004, the midpoint of the Bush presidency. A coalition of states and private land trusts, led by the State of Connecticut, that were frustrated with Washington’s failure to introduce legislation or regulations limiting greenhouse gas emissions sued several of the nation’s largest electric utilities in Connecticut v. American Electric Power. The coalition alleged that the companies’ greenhouse-gas emissions amounted to a “public nuisance” in the form of global warming. Under the nuisance principle — one of the oldest in English common law — a property owner may ask the court to stop a defendant who is interfering with the owner’s enjoyment of his own property, and, in some circumstances, to pay damages. In the Connecticut case, the plaintiffs thus sought to persuade the court to order the utility companies to reduce their greenhouse-gas emissions by showing how such gases cause global warming, which in turn was creating increased temperatures, alternating drought and floods, destruction of natural habitats, and corresponding decreases in property values and human health and welfare.

Though the cause-and-effect aspect of this argument might seem hard to prove in court, global-warming victims in other corners of the country started filing similar lawsuits. In Comer v. Murphy Oil, residents of Mississippi’s Gulf Coast sued nearby oil refineries for damages they suffered during Hurricane Katrina, alleging that the refineries’ greenhouse-gas emissions contributed to the force of the storm. In 2008, in Native Village of Kivalina v. Exxon, residents of a small village on a barrier island off the Alaskan coast, whose homes are being steadily submerged by rising sea levels, filed suit against two dozen energy companies for their contribution to climate change. The villagers, who are native Inupiat, seek more than $400 million in damages to cover the cost of relocating their homes, again using the doctrine of nuisance law.

Each of these cases was dismissed at the trial court level. The judges said that the suits raised a “political question” not fit for the judicial branch to rule on-a tool that allows judges to punt tricky cases they don’t want to decide. Two of the lower courts also said that the parties lacked legal standing to bring the lawsuits, because they could not show their injuries were sufficiently traceable to the defendants’ conduct. However, the plaintiffs appealed these dismissals to federal courts of appeals, arguing that they do have standing and that the “political question” doctrine does not apply.

Then, to the shock of the legal community and even some environmentalists, two federal appeals courts reversed these rulings. Last September, after more than three years of deliberating, a two-judge panel on the U.S. Court of Appeals for the 2nd Circuit overturned the dismissal of Connecticut v. AEP in a sweeping 139-page opinion. A few days later, a three-judge panel of the U.S. Court of Appeals for the 5th Circuit released a similar opinion reinstating the Katrina victims’ lawsuit. The five judges responsible for these rulings-three of whom were appointed by Republican presidents-found that the plaintiffs had standing and that the evidence of the relationship between greenhouse gases and climate change was sufficient for the cases to go forward. The courts did not punt because of the “political question” doctrine, pointing out that federal courts have successfully handled public nuisance claims involving environmental damage for more than a century.