Science, Attribution Studies, & Identifying Climate Criminals

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The word “science,” according to Wikipedia, is derived from the Latin verb “scire, meaning ‘to know,’ specifically its present participle sciens, meaning ‘knowing.’” The root word scire is also connected to English words like conscience — shared knowledge of right and wrong — and omniscient — all-knowing. My, how times change. Today, in the world of MAGA maniacs, a scientist is someone who sucks precious funds out of the federal budget in order to write learned treatises on the economic importance of protozoa while eating bonbons in St. Tropez.

It is common knowledge that the Earth has grown significantly hotter since the beginning of the Industrial Age. Why, is the question. If you are reading CleanTechnica, you probably know the answer — carbon dioxide from burning fossil fuels and methane pollution. But if you are a fossil fuel company, that conclusion is terrifying because it could lead to a.) an end of obscene profits, and b.) financial responsibility for the damage your products have caused.

So, what do you do? Why, you hire a flotilla of highly trained lawyers to cover your tracks using the tried and true “deny, deny, deny” tactics developed by other lawyers who built a legal shield around the tobacco industry. Writing in Mother Jones, Rachel Santarsiero tells of one such lawyer, Michael Buschbacher, a partner at Boyden Gray, who posed this question during a Federalist Society panel on climate litigation last October: “How can you show proximate causation in injury? Bad weather is of course not new. So how do you show that emissions from company X cause injury Y from a hurricane or whatever?”

He then wondered about the consequences of the suits should they be successful. “Will they reduce global carbon emissions, or will it just be a payday for contingency fee lawyers and opportunity for virtue signaling from progressive politicians?” Buschbacker quite obviously believes himself morally superior to those shysters in the personal injury world who flit about in private jets as they troll for clients for their next big class action lawsuit.

He has a point, of course. John Grisham in his book The King Of Torts detailed exactly how that game is played. In Shakespeare’s Henry VI, Part 2, Dick The Butcher said: “The first thing we do, let’s kill all the lawyers.” In other words, a pox on all their houses. But his other point is valid as well.

Every first-year law student knows the story of poor Mrs. Palsgraf, who was injured on railroad property when a gang of juvenile miscreants began tossing fireworks about. That case is often cited as the foundation for all personal injury law in the United States because it introduced the concepts of “foreseeability” and “proximate cause” into the legal conversation. 200 years later, Michael Buschbacker is telling the folks at the Federalist Society (all six of the current US Supreme Court were members of the Federalist Society or influenced by it) that the Palsgraf case is still relevant today and can be used to shield them from liability for their deliberate decisions to degrade the environment in the pursuit of profits.

Prove It!

A study by Christopher Callahan of the Oneill School of Public and Environmental Affairs at Indiana University published August 7, 2026, in the journal Earth’s Future may provide the level of attribution needed to explode the legal defenses erected by Michael Buschbacker and his ilk. It is entitled Extreme Heat and Rainfall Risk Attributed to Cumulative CO2 Emissions from Fossil Fuel Producers. Here is the abstract to that study:

“Legal and political approaches to climate accountability require demonstrating that a particular emitter contributed to a climate impact, but quantitative solutions to this attribution challenge remain nascent. This study leverages the proportionality of global warming to cumulative CO2 emissions to develop statistical models that directly predict extreme climate risk from cumulative emissions.

“Results show that cumulative emissions from individual actors have increased the probability of extreme heat and rainfall globally; for example, emissions from the United States have increased the risk of recent extreme heat by at least 50 percent for one third of the globe. Focusing on specific events demonstrates that emissions from major fossil fuel firms increased the likelihood of the 2021 Pacific Northwest heat wave by 31 percent and 2022 extreme rainfall in Pakistan by 7 percent. These results demonstrate a flexible attribution framework grounded in the proportional relationships that inform climate policy, with the potential to guide efficient climate accountability assessments.

Plain Language Summary

“It is difficult to determine which fossil fuel emitter contributed to an extreme climate event like a heat wave or a flood. To help close this gap, this paper shows that there is a direct proportionality between cumulative carbon dioxide emissions and the probability of extreme heat and rainfall. As a result, given the contributions that major countries and fossil fuel producers have made to historical emissions, their contributions to the increasing risk of extreme heat and rainfall can be directly inferred.

“This approach can be flexibly applied to many types of emitters at any location or time; for example, it can be used to show that emissions from ExxonMobil, Chevron, and other major fossil fuel producers increased the risk of extreme heat in the Pacific Northwest. This framework has the potential to inform future assessments of the liability of major emitters for extreme heat and rainfall.”

Identifying Emitters

Rachel Santarsiero wrote that for the first time, drawing a straight line from single corporate emitters like Exxon or Chevron, or even whole countries like the United States, to specific heatwaves and areas of extreme rainfall is now possible. “By running over 150 simulations across 8 different climate models, Callahan … built a statistical model to figure out the relationship between the amount of carbon dioxide in the atmosphere and the odds of extreme heat or rain. He then used real emissions data to calculate the extent to which specific fossil fuel emitters increased the risk of extreme weather.” The study’s results are clear: “There is no level of emissions that does not contribute to changing climate impacts,” Callahan said. “Every ton matters.”

The implications of this for an industry struggling to contend with the potential consequences of its actions could be dire. “Climate attribution research seeks to connect greenhouse gas emissions to specific climate impacts, and increasingly, to particular industries or companies,” wrote Kyle Kohli in Energy In Depth, a blog associated with the Independent Petroleum Association of America. “That makes it especially valuable to climate plaintiffs attempting to overcome one of their biggest legal obstacles: proving causation.”

In the past, source attribution studies linked several climate models that were, in Callahan’s words, “computationally difficult,” sometimes taking months to run and requiring vast amounts of computing capacity. “The approach here is attempting to be particularly simple and particularly lightweight,” Callahan explained. Now, by knowing the proportions between climate change and cumulative emissions, he said, researchers can calculate changes to extreme events based on historical emissions. “What this science tells us is that there is a direct relationship between how much an entity emits and … [the] extreme events that alter people’s lives.”

Sowing Doubt

For more than 50 years, the fossil fuel industry has known about and misled the public about its role in human-caused planetary warming, deliberately sowing doubt to undermine scientific evidence. Now oil and gas groups are facing a wave of lawsuits. Over 40 cases in the United States filed by states, municipalities, and tribal governments have been brought against Big Oil since 2017. At least five of these lawsuits have entered the discovery phase — marking a turning point that could force oil executives to hand over key documents and testify under oath on what they knew about climate change and when they knew it. Grist reported in July that the American Petroleum Institute, the largest oil lobbying group, stated that one of its top priorities for 2026 was to “stop extreme climate liability policy.”

Callahan has no illusions about how his research will fit into the current legal and political climate, describing it as “a pretty live question in conversations around climate liability lawsuits.” But how will attribution science play out in a legal context? Some experts argue that it will “[rock] the courtroom,” while others say key decisions will most likely hinge on legal issues rather than the science itself. “Our responsibility as scientists,” Callahan said, “is not to never do science that is relevant to the political conversation. We should follow the results of our questions wherever they lead and report them regardless of what they are.”

Attacking The Science

An investigation by Politico in June revealed a secret opposition campaign waged by oil industry allies to discredit the report’s findings. The campaign came just months after Republican attorneys general successfully forced the removal of a NAS climate sciences chapter from a reference manual for federal judges, which the Academies officially pulled earlier this month. A NASA scientist who asked to remain anonymous called the academy’s decision to pull the chapter “pathetic. If they cannot stand up for science, then who is going to?”

“I thought it was a great report,” said Michael Mann of the University of Pennsylvania. “It didn’t pull any punches.” Others, like Kristina Dahl, a climate scientist and vice president for science at Climate Central, said the report was “a really excellent roundup of the state of the science.”

Reports like the Academies’ extreme weather event attribution study and Callahan’s research on emitter impacts help illustrate how far the field has come. “We all live in a world that’s been shaped by a fossil fuel-based economy,” Dahl said, “so I think studies like this can shed light on why we are where we are, and why we have the range of choices available to us that we have, and can also give us a sense of how different the world would be.”

Poor Mrs. Palsgraf never realized how her lawsuit against the Long Island Railroad would open the door to a whole new chapter in how the law treated risk and its consequences. It has followed a long and tortured path over the past 200 years. Perhaps this new research by Christopher Callahan will open a new phase on climate litigation, which is why the fossil fuel industry is in a panic to get Congress to pass legislation giving it immunity for any verdicts against it. With Republicans who voluntarily surrendered their testicles to the MAGA Madness a decade ago in control of the government, such a thing is entirely possible.

And yet, science cannot be denied, as illustrated by this iconic video by Thomas Dolby: