Climate Change Science and the Daubert Standard
By Fred K. Morrison, Craig Manson and Matthew C. Wickersham
Climate change science attempts to predict the future based on complex modeling of potential levels of CO2, other greenhouse gases, manmade conditions, and naturally occurring events. Even the most widely cited analysis of climate change studies expressly acknowledges the limitations on accurately predicting the effects of climate change on anything other than a macro basis.1 These studies acknowledge substantial uncertainty in the prediction of climate change and its effects on a regional level, much less on a local level.2 Recent lawsuits brought by the State of Rhode Island; the counties of King (Washington), Marin (California), and San Mateo (California); the cities of New York, San Francisco, Oakland, Santa Cruz, Imperial Beach, Richmond (California), Baltimore, and Boulder; and the Pacific Coast Federation of Fishermen’s Associations against certain oil companies seek funds for anticipated localized impacts of climate change, including rising sea levels, drought, and wildfires.3 If these cases survive various justiciability challenges, plaintiffs’ expert testimony supporting its claims will likely be challenged under Daubert v. Merrell Dow Pharmaceuticals, Inc., the California Supreme Court’s decision in Sargon Enterprises, Inc. v. University of Southern California, and other state court equivalents on the grounds that the science underlying plaintiffs’ claims is not sufficiently reliable to be admitted into evidence.4 This Article explores the reasons why such plaintiffs’ climate change theories and damages allegations must be carefully scrutinized under Daubert and Sargon and why the expert theories underlying plaintiffs’ claims will likely be held inadmissible.Conclusion Climate models are not sufficiently reliable to allow for the admission of expert opinions regarding a particular actor’s contribution to global warming in a localized region of the world. These climate models are not appropriate for and do not support the “particularized resolution of legal disputes.”168 Accordingly, expert opinions based on these models are properly excluded as insufficiently reliable.