As a state whose lifestyle and economy are profoundly dependent on how much and how soon the planet warms, New Hampshire should absolutely join nearly a score of other state attorneys general in the investigation of Exxon’s effort to forestall climate change legislation.

Exxon, in an investigation launched by the Pulitzer Prize-winning online journalism site Inside Climate News, was found to have ignored its own scientists’ findings that climate change is real and driven in the main by burning fossil fuels.

In the 1980s, Exxon, which paid for a ship to monitor carbon dioxide levels on the world’s oceans, shared its research and urged concern.

In the late 1970s, company spokesman Richard Kell reportedly said: “At all times the opinions and conclusions of our scientists and researchers on this topic have been solidly within the mainstream of the consensus scientific opinion of the day and our work has been guided by an overarching principle to follow where the science leads. The risk of climate change is real and warrants action.”

When it became clear that its own research could lead to restrictions on fossil fuels, it reversed course and funded climate change denial groups.

The evidence, in the form of thousands of pages of documents already obtained by investigators, is damning. It shows, though Exxon now disputes this, that the company concluded that publicizing the growing problem could threaten the company’s very existence. Fellow fossil fuel extractors agreed and joined the disinformation campaign.

Less conclusive, or so it seems to us, is whether by suppressing its evidence and touting the opposite, Exxon broke the law. If legal action is taken, it could come in a number of forms. At the top of the list is fraud under the Securities Exchange Act, which requires that companies provide investors with accurate information about factors that could affect the profits and the company’s future. Exxon predicted climate change would, and it is.

Also possible are charges under the RICO organized crime act, the law used against the tobacco companies that led to massive payments to the states. New Hampshire may or may not get any money that could be used, say, to upgrade culverts or help Seacoast communities prepare for rising sea levels. But if the investigation shuts off fossil fuel-state politicians like Senate Majority Leader Mitch McConnell of Kentucky and leads to the passage of the Clean Power Act, it will have done its job.