Back in the dim past, society entered into a great debate about the health effects of cigarette smoking, a noxious habit I practiced myself for many years. There were always those who found the practice objectionable, some for reasons of hygiene (it was a dirty habit) and some for reasons of morality (it was a sin). Eventually evidence accumulated that it was more than just dirty or sinful, but that it was grave danger to one’s health. Most pernicious was the evidence that it caused lung cancer.

I accepted the evidence—it seemed intuitive that pumping smoke into one’s lungs couldn’t help but do damage—but I didn’t blame the cigarette companies. My view was one of caveat emptor. If you choose to smoke, the results are on you—you take your chances.

My view changed when it was revealed that the companies had known for years, well before it was public knowledge, that their product caused cancer. And, furthermore, they had taken measures to conceal or cast doubt on the knowledge. For this, it seemed to me, the companies deserved to be held accountable for. So I redirected much of my blame and supported the massive lawsuits that were brought against them.

I have followed a similar path with the oil companies. For a long time, I have placed the blame for global warming largely on we the public. We want the oil and gas to drive our cars and heat our homes (and make our plastic) and the companies just respond to our bidding.

Now it turn out that at least one oil company, ExxonMobil, has followed the tobacco companies’ playbook. It knew for years that its products caused global warming, yet kept the knowledge secret and engaged in efforts to create doubt about the science.

According to the journal Science, “In private and academic circles since the late 1970s and early 1980s, ExxonMobil predicted global warming correctly and skillfully … the same as that of independent academic and government projections.… But whereas those scientists worked to communicate what they knew, ExxonMobil worked to deny it—including overemphasizing uncertainties, denigrating climate models, mythologizing global cooling, feigning ignorance about the discernibility of human-caused warming, and staying silent about the possibility of stranded fossil fuel assets in a carbon-constrained world.”

And they weren’t alone. Again quoting Science, “The US oil and gas industry’s largest trade association had likewise known since at least the 1950s, as had the coal industry since at least the 1960s.”

I certainly wouldn’t have doubted the validity of Exxon’s science. I worked for Shell Canada for a number of years and was always impressed by the quality of the industry’s engineering and science, of which I was a part.

The industry was very good to me, so I find no satisfaction in recognizing its deceit. But I can’t disagree with Martin Hoffert, one of the first scientists to create a model predicting the effects of man-made climate change while employed by Exxon. Hoffert quit in anger, saying. “What they did was immoral. They spread doubt about the dangers of climate change when their own researchers were confirming how serious a threat it was.”

Exxon now claims to be on the side of the angels. According to ExxonMobil CEO Darren Woods, “We respect and support society’s ambition to achieve net zero emissions by 2050, and continue to advocate for policies that promote cost-effective, market-based solutions to address the risks of climate change.”

But it’s too late, Mr. Woods, even if those “market-based solutions” would work. Your company and industry are being sued by a host of jurisdictions for deceptive marketing, misleading shareholders, and culpability for climate damages. I wish all of them the best of luck.