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Exxon is under investigation for possible lies about climate

For months, a protest movement known as "Exxon Knew" has been rallying for an official investigation into the oil giant. This week that investigation arrived.

This article has been updated.

For months, a protest movement known as "Exxon Knew" has been rallying for an official investigation, a call to action inspired by reports that Exxon had confirmed the risks of catastrophic climate change -- only to deny and undermine those findings for decades publicly. This week that investigation arrived.  

New York Attorney General Eric Schneiderman launched the probe late Wednesday (and CNBC confirmed it Thursday afternoon), subpoenaing the company -- now known as the ExxonMobil -- and demanding extensive financial records, emails and other documents related to climate research.

A global scientific consensus says that greenhouse gas emissions are heating the planet, roiling the atmosphere and threatening the world as we know it with irreversible damage. If economies keep burning the oil, gas, and coal that produce the majority of these gases, the climate could become unmanageable within decades, according to the Intergovernmental Panel on Climate Change.

WATCH: Could ExxonMobil go the way of big tobacco?

At issue in the New York state investigation is whether ExxonMobil -- one of the world's biggest oil companies -- confirmed the climate destabilizing role of carbon emissions but misled the public about what they knew. Investors are also a potentially wronged party: the New York attorney general is looking at whether the company prepared shareholders for how a policy response to climate change could hurt the company's oil business. 

"We have received a subpoena for production of documents relating to climate change from the attorney general of New York and are assessing our response," Exxon said in a statement to CNBC. "We unequivocally reject allegations that ExxonMobil suppressed climate change research contained in media reports that are inaccurate distortions of ExxonMobil’s nearly 40-year history of climate research that was conducted publicly in conjunction with the Department of Energy, academics and the UN Intergovernmental Panel on Climate Change." 

In the past year, separate major reporting projects by the Union for Concerned Scientists, the nonprofit InsideClimate News, and a team from Columbia University and The Los Angeles Times have set down a timeline for what the energy company knew and when it knew it. The reports suggest that the company's scientists had confirmed the dangers of climate change as early as 1977, more than decade before NASA scientist James Hansen briefed Congress and activist Bill McKibben wrote a bestselling book for the general public. 

WATCH: Exxon knew four decades ago about CO2

The New York state investigation follows rising calls for action not only from activists, but from the three leading Democratic presidential candidates and many members of Congress. Former Maryland Gov. Martin O'Malley was the first to speak up, tweeting on Oct. 16: "We held tobacco companies responsible for lying about cancer. Let’s do the same for oil companies & climate change." 

“Based on available public information, it appears that Exxon knew its product was causing harm to the public, and spent millions of dollars to obfuscate the facts in the public discourse.”'

Vermont Sen. Bernie Sanders followed suit on Oct. 20, sending a letter to Attorney General Loretta Lynch. He called for a federal investigation into not only Exxon, but the other oil major companies, many of which have been accused of funding groups that undermine the consensus on climate change.  

“These reports, if true, raise serious allegations of a misinformation campaign that may have caused public harm similar to the tobacco industry’s actions,” Sanders wrote. “Based on available public information, it appears that Exxon knew its product was causing harm to the public, and spent millions of dollars to obfuscate the facts in the public discourse.”

Hillary Clinton followed her more progressive competitors, voicing her support late last month after a town hall event in Berlin, New Hampshire. She was asked whether federal investigators should act based on what's been reported about Exxon.

"Yes, yes, they should," Clinton replied. "There's a lot of evidence that they misled people."

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None of the major GOP presidential candidates have called for an investigation. But many observers see parallels between the gathering Exxon case and the big tobacco case of the 1990s. In 1999, the Department of Justice sued Phillip Morris and several other major tobacco companies for fraud. One specific charge: misleading the public about the risks of smoking. In 2006 a judge agreed, ruling that the tobacco companies had covered up the health risks of cigarettes and marketed to children.

The outcome of the Exxon investigation is still many years away. The company has not been hit with a lawsuit or charged, and may never be. The "consensus" on climate change is also, in fact, much older and more robust than Exxon in the 1970s. Federally-funded scientists were studying climate change back in the 1960s.

In 1965, President Lyndon Johnson's Science Advisory Committee warned that we "will modify the heat balance of the atmosphere" if we keep burning fossil fuels. President Johnson himself took up the issue in a special message to Congress. "This generation has altered the composition of the atmosphere on a global scale," he said, and he named a culprit: "a steady increase in carbon dioxide from the burning of fossil fuels."

Still, critics say that Exxon had an extraordinary role in sowing public confusion, and deserves to pay an extraordinary price.

"Just as New York’s Teddy Roosevelt took on the Standard Oil Trust a century ago, New York’s attorney general has shown great courage in holding to account arguably the richest and most powerful company on Earth," McKibben, the activist and author, said. "We hope that other state attorney generals and the federal Department of Justice, and the Securities Exchange Commission will show similar fortitude."