Attribution science can help fill the evidentiary gap in climate suits
The branch of climate science known as attribution science has improved considerably in the last 15 years. In the past, the degree of certainty as to whether increasing greenhouse gas emissions led to an increase in extreme weather around the world has been a bit fuzzy. Today, scientists can say with great accuracy that specific events were caused, or made more likely by, the climate crisis.
For example, a study by the World Weather Attribution Association demonstrated that the recent extreme heat in Western North America would have been virtually impossible without human-caused climate change. This greater level of accuracy in attribution science is extremely promising for climate litigation, as the strength of evidence can bolster claims and give a strong evidentiary basis to substantiate claims against states and corporations. Such studies could also help courts considering lawsuits that allege that government agencies or private companies have failed to prepare for, or have contributed to, the effects of climate change and should thus be held accountable.
To date there have been more than 1,800 climate suits filed world-wide. Climate science plays a central role in supporting the arguments in these cases. Unfortunately, the vast majority of these cases have been unsuccessful, largely due to the evidentiary gap given that causality is a key aspect in these cases. Courts have previously rejected links between companies’ and states’ polluting activities and damages to the climate or extreme weather events due to the lack of strong evidence. More accurate and up to date climate science can help lawyers and claimants overcome these barriers.
The most recent IPCC report will help support strong climate action, but as litigation expands in scope and novel claims appear, lawyers will need to draw on a broad range of research. IPCC reports are usually held as the gold standard of accepted climate research, but there are reasons to incorporate other science in the courts. IPCC reports are gargantuan studies that take years to compile, and given the pace of atmospheric warming and extreme weather events, the results may be out of date by the time they are published. Attribution science can help fill this gap, as can reviews of countries’ compliance to Paris commitments, and corporations’ ESG disclosures.
Researchers out of Oxford’s Sustainable Law Programme recently published a study which examined 73 lawsuits, and found that many had failed to use the latest science in their evidence. They concluded that the chances of success would have been improved if they had used the latest science, which evinces a clearer link between the companies’ and states’ actions giving rise to carbon emissions that lead to rights violations and damages caused by extreme weather. If more cases that rely on new climate science are successful, this could incentivize corporations and financial institutions to see their emissions as liabilities which present a legal risk, and thus act.