Climate change litigation and attribution science

Climate change litigation and attribution science

Climate change litigation and attribution science 500 273 Bob Reville

Climate change tort litigation has faced significant obstacles to establishing corporate liability for climate change. Cases such as Kivalina v. ExxonMobil, and California v. General Motors Corporation faced significant obstacles based in tort legal doctrine and were ultimately unsuccessful in establishing liability. In the article cited below, the authors (Marjanac and Patton) suggest a second wave of climate change litigation is waiting to happen due to the advances in a new area of science called “extreme weather attribution science.”

At Praedicat, we spend a great deal of time analyzing and modeling “general causation,” which we affectionately call GC and have developed a quantitative score to measure it. GC addresses whether a harm alleged in litigation can, in principle, have been caused by the defendant’s action. By “in principle,” we mean “by science,” so in other words, do scientists believe that it is possible that the defendant’s action could have caused the plaintiff’s harm? On climate change, the general causation question is could carbon emissions, in principle, have caused the climate harm in question, such as wildfires. Increasingly, the GC questions for climate change are settled (at least among scientists). Carbon emission can increase the likelihood of wildfires, or hurricanes, or coastal flooding, and many other harms. (At Praedicat, we don’t yet search and score these literatures since we focus on bodily injury and bioscience, but stay tuned!)

The problem in climate change litigation, though, is frequently not general causation, but specific causation. Specific causation goes a step further than GC and says that this specific plaintiff’s harm was caused by this specific defendant’s product or action. Sometimes, the plaintiff is helped by the fact that he or she may have a “signature disease,” which is only caused by the product in question. In asbestos, for instance, mesothelioma is the “signature disease” of asbestos. In contrast, if a wildfire consumes a house, we might be comfortable with the idea that carbon emissions increase the risk of wildfire, but it is another thing altogether to say that wildfires are exclusively caused by carbon emissions. This will make climate change litigation over wildfires challenging for the plaintiffs.

Extreme weather attribution science looks to change this. It seeks to find the signature diseases of carbon emission. The article cites the example of unprecedented heat waves, such as occurred in Asia in 2016 resulting in hundreds of deaths, where the weather pattern is outside the feasible range of natural variability. If the courts accept this kind of evidence, there will still be other significant challenges to establishing liability, but the prospects for climate change litigation will be much better than they were in the “first wave.”

Climate change has additional hurdles, primarily in relation to establishing a duty of care, as well as standing and justiciability issues, which led to the early dismissal of the majority of tort-based claims against major emitters and producers of greenhouse gases.