Fossil fuel companies actively campaigned to create doubt about the climate crisis and the steps needed to undo the damage, according to a report by an international group of scientists – revealed on the same day the oil and gas giant ExxonMobil is set to face trial for lying to its shareholders.

Researchers from Harvard, George Mason University and the University of Bristol looked at more than a decade of peer-reviewed research and concluded internal corporate documents show that the fossil fuel industry has known about human-caused climate change for decades.

The response of the companies, the research showed, was to actively arrange and fund denial and disinformation to suppress action and protect its status quo business operations. Companies used different tactics such as championing conspiracy theories, promoting fake experts and cherry-picking scientific evidence.

“For 60 years, the fossil fuel industry has known about the potential global warming dangers of their products,” said Geoffrey Supran, the study author. “But instead of warning the public or doing something about it, they turned around and orchestrated a massive campaign of denial and delay designed to protect profits.”

The report showed that companies attacked at the scientific consensus behind climate change, with over 97% of the scientists agreeing it’s a man-made problem. Companies carried out market research to confuse the public on that consensus, despite they knew regarding climate change since 1950.

“Disinformation about climate change has a straightforward purpose—to block action on climate change. In America, it has largely succeeded, with policies to mitigate climate change stymied or delayed for decades,” the report reads. “Meanwhile, climate change has intensified, causing impacts.”

Lawsuit on Exxon

Oil industry giant Exxon Mobil went to court today in the US to face charges that the company lied to shareholders and to the public about the costs and consequences of climate change. It’s the second climate-change lawsuit to reach trial in the country.

The company is claimed to have kept a secret set of financial books that seriously underestimated the costs of potential climate change regulation while claiming publicly that it was taking such factors into account.

Exxon has fought the charges, arguing that they were politically motivated and should have been thrown out. It maintains that the government’s theory of its financial tools is flawed at best and, at worst, disingenuous.

Exxon has long conducted research into climate change and published much of it in the scientific literature. In 2015, Inside Climate News and The Los Angeles Times used materials from corporate archives to show the extent of that research and how it was used in long-term planning, even while the company was funding groups that sought to spread doubt about climate science.

More than 1,000 climate change lawsuits have been filed in the United States, said Michael Gerrard, founder of the Sabin Center for Climate Change Law at the Columbia University Law School. The first was brought more than a decade ago by automotive industry companies to challenge Vermont’s ability to set emissions standards.