This story was originally published by Grist and appears here as part of the Climate Desk collaboration.

A new legal theory suggests that oil companies could be taken to court for every kind of homicide in the United States, short of first-degree murder.

The idea of “climate homicide” is getting attention in law schools and district attorney’s offices around the country. A paper published in Harvard Environmental Law Review recently argues that fossil fuel companies have been “killing members of the public at an accelerating rate.” It says that oil giants’ awareness that their pollution could have lethal consequences solidly fits within the definition of homicide, which, in its basic form, is causing death with a “culpable mental state.” In other words, the case can be made that oil companies knew what they were doing.

“It’s sparking a lot of conversation,” said Aaron Regunberg, senior policy counsel at the advocacy group Public Citizen. After discussing the idea with elected officials and prosecutors, Regunberg said many of them have moved from “‘Oh, that’s crazy’ to ‘Oh, that makes sense.’”

Starting around the 1970s, oil companies like Exxon understood the dangers that burning fossil fuels would unleash — unprecedented warming that would render parts of the globe “less habitable,” submerge coastal cities and lead to extensive drought and mass famine. Yet instead of switching away from coal and oil, they doubled down, working to block legislation to reduce greenhouse gas emissions and spreading doubt about the science of climate change. Today, with atmospheric CO2 climbing to levels last seen 14 million years ago, the predicted consequences have begun to arrive. Since the start of the 21st century, climate change has killed roughly four million people, according to one conservative estimate.

By 2100, that same number of people could be killed by the effects of climate change every single year, according to the new paper by David Arkush, the director of Public Citizen’s climate program, and Donald Braman, a law professor at George Washington University. “[T]he scope of the lethality is so vast that, in the annals of crime, it may eventually dwarf all other homicide cases in the United States, combined,” they write.

Criminal law cases are normally brought against individuals, but Regunberg says there’s a strong case for applying it more broadly. “It’s supposed to be about protecting us from dangerous actors that would harm our communities. What if we actually use this system to protect us from dangerous corporate actors that are doing incomprehensible harm?”

Homicide opens up a new flank in the strategy to bring climate change into the courts. Climate litigation is now in its “third wave,” according to Anthony Moffa, a professor at the University of Maine School of Law. The first lawsuits sought to force power companies to limit their emissions by way of federal public nuisance claims, a strategy the Supreme Court shot down in 2011. Then people started suing the U.S. and state governments using the argument that they had a duty to protect their citizens from climate change. The approach bore fruit last year when young climate activists won a suit against Montana that claimed the state’s failure to evaluate climate risks in approving fossil fuel projects violated their constitutional right to a healthy environment.

That phase also includes a flood of climate lawsuits filed against oil companies in state courts using laws meant to protect people from deceptive advertising, and those cases are finally moving closer to trial after years of delays. Now the strategy has expanded to include racketeering lawsuits, which use the laws that took down the Mafia against Big Oil, and potentially criminal law cases including homicide or reckless endangerment.

Taking Big Oil to court for ‘climate homicide’ isn’t as far-fetched as it sounds. #ClimateHomicide #ClimateChange #ClimateLitigation #ClimateLawsuits #BigOil

Arkush and Braman’s paper suggests that all types of homicide are on the table except for first-degree murder, which requires premeditated intent. One option is “involuntary manslaughter,” or engaging in reckless conduct that causes death, even if it’s unintentional. “Negligent homicide” is similar, but for neglectful behaviour. There’s also “depraved heart murder,” which requires engaging in conduct where you knew there was a substantial risk someone would be killed. Other variants include “felony murder” and “misdemeanour manslaughter.” Criminal law differs between states, so an attorney general or district attorney’s approach would depend on the jurisdiction.

Homicide suits could be a powerful force for holding oil companies accountable and forcing them to change their polluting ways. “Where tort law merely prices harmful conduct, criminal law prohibits it — and provides tools to stop it,” Arkush and Braman wrote in the Harvard Environmental Law Review paper. A successful lawsuit could result in courts requiring fossil fuel companies to restructure as “public benefit corporations” that have to balance profits with a commitment to the public good, replace their boards with new members, or make legally binding commitments to forgo certain practices.

To promote the idea of “climate homicide,” Public Citizen has been organizing panel discussions in recent weeks at law schools including Yale, Harvard, the University of Pennsylvania, New York University, and the University of Chicago. Public Citizen is also looking into staging mock trials to see how jurors might react to these kinds of cases and what evidence they find compelling.

“There are a number of prosecutorial offices that seem interested in giving these legal theories serious consideration,” Regunberg said. “They understand that climate disasters — extreme heat, wildfires, floods, and more — are endangering their communities, and if there’s a way to stop criminally reckless conduct that’s contributing to these threats, they’re going to explore that possibility.”

The idea has been embraced by Sharon Eubanks, who led the United States’ racketeering lawsuit against tobacco companies in 2005, in which the court found that companies had conspired to deceive the public by covering up the health dangers of smoking. “There were a lot of people who said we were crazy to charge big tobacco with racketeering and that we could never win,” Eubanks told The Guardian. “But you know what? We did win. I think we need that same kind of thinking to deal with the climate crisis.”

So why has no one seriously considered suing oil companies for homicide until now? Recent years have brought advances in the science that connect climate change to extreme weather events and quantify how corporate emissions have fuelled disasters like wildfires, paving the way for these types of cases. Still, the need to include attribution science adds a layer of complexity that hasn’t been present for similar litigation against tobacco or opioid companies, according to Moffa.

And then there’s the fact that prosecutors are reluctant to take corporations to court with criminal law charges. The first time that a corporation was charged under a criminal statute for manslaughter was in 1904, when a steamship owner was found guilty after its ship caught fire and 900 passengers drowned, but the legal strategy never really took off. “So then to say, ‘Why haven’t they ever done this in the environmental law?’ They haven’t really done it in almost any context,” Moffa said.

In their paper, Arkush and Braman argued that fossil fuel companies have been acting as if they were above the law. “Under a plain reading of the law in jurisdictions across the United States, they are committing mass homicide,” they conclude. “Prosecutors should act accordingly.”

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