In one of the nation’s first wrongful-death claims seeking to hold the fossil fuel industry accountable for its role in the changing climate, a Washington state woman is suing seven oil and gas companies, saying they contributed to an extraordinarily hot day that led to her mother's fatal hyperthermia.

The lawsuit filed in state court this week says the companies knew that their products have altered the climate, including contributing to a 2021 heat wave in the Pacific Northwest that killed 65-year-old Juliana Leon, and that they failed to warn the public of such risks.

On June 28, 2021, an unusual heat wave culminated in a 108-degrees Fahrenheit (42.22 degrees Celsius) day — the hottest ever recorded in the state, according to the filing. Leon had just driven 100 miles from home for an appointment, and she rolled down her windows on the way back because her car's air conditioning wasn't working.

Leon pulled over and parked her car in a residential area, according to the lawsuit. She was found unconscious behind the wheel when a bystander called for help. Despite medical interventions, Leon died.

The filing names Exxon Mobil, Chevron, Shell, BP, ConocoPhillips, Phillips 66 and BP subsidiary Olympic Pipeline Company. ConocoPhillips, BP and Shell declined to comment when reached by The Associated Press. The other companies did not respond to requests for comment.

“Defendants knew that their fossil fuel products were already altering the earth’s atmosphere,” when Juliana was born, Thursday's filing said. “By 1968, Defendants understood that the fossil fuel-dependent economy they were creating and perpetuating would intensify those atmospheric changes, resulting in more frequent and destructive weather disasters and foreseeable loss of human life.”

The filing adds: “The extreme heat that killed Julie was directly linked to fossil fuel-driven alteration of the climate."

The lawsuit accuses the companies of hiding, downplaying and misrepresenting the risks of climate change caused by humans burning oil and gas and obstructing research.

International climate researchers said in a peer-reviewed analysis that the 2021 “heat dome” was “virtually impossible without human-caused climate change.”

Scientists have broadly attributed the record-breaking, more frequent, longer-lasting and increasingly deadly heat waves around the world to climate change that they say is a result of burning fossil fuels. Oil and gas are fossil fuels that, when burned, emit planet-warming greenhouse gas emissions, such as carbon dioxide.

“We’ve seen a really advanced scientific understanding about this specific effects that climate change can cause in individual extreme weather events,” said Korey Silverman-Roati, a senior fellow at the Columbia Law School's Sabin Center for Climate Change Law. “Scientists today are a lot more confident in saying that but for climate change, this would not have happened."

Silverman-Roati said the specificity of the case could clarify for people the consequences of climate change and the potential consequences of company behavior.

The lawsuit was first reported by The New York Times.

Unprecedented action

States and cities have long gone after fossil fuel industry stakeholders for contributing to the planet’s warming — somewhat unsuccessfully. Hawaii and Michigan, for example, recently announced plans for legal action against fossil fuel companies for harms caused by climate change, and they have been met by a counter lawsuit from the U.S. Justice Department.

But this is one of few cases that looks to argue these companies should be held liable for an individual’s death. Misti Leon is seeking unspecified monetary damages.

“Big Oil companies have known for decades that their products would cause catastrophic climate disasters that would become more deadly and destructive if they didn’t change their business model,” said Richard Wiles, president of the Center for Climate Integrity, said in a statement on the case. “But instead of warning the public and taking steps to save lives, Big Oil lied and deliberately accelerated the problem."


Alexa St. John is an Associated Press climate reporter. Follow her on X: @alexa_stjohn. Reach her at ast.john@ap.org.


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