Attribution science and global climate litigation
The claim in Shell/Odette is made in the context of a marked increase in climate harm-related claims globally,1 many of which have sought to use attribution science to establish a causal link between the GHG emissions of businesses and climate-related harm.
In the recent German case of Lliuya v RWE,2 a Peruvian farmer sought damages against the parent company of RWE, a multinational energy group. The claimant argued that his home in the town of Huaraz in Peru was at risk of climate-related harm, and that RWE was liable for the resulting mitigation costs. He claimed compensation proportionate to RWE's estimated contribution (c. 0.47%) to total global GHG emissions since the start of the industrialised era.
The German court eventually dismissed the claim on the basis that the claimant's property was not in fact at substantial risk of climate-related harm. However, it accepted that attribution science could establish a sufficient causative link between major GHG emitters and climate-related harm, and concluded that major emitters can be liable for such harm in proportion to their contribution to GHG emissions.
The role of attribution science in establishing causation was also considered in the New Zealand case of Smith v Fonterra3. In that case, the claimant alleged that the GHG emissions of seven businesses amounted to a public nuisance and sought declarations and injunctions accordingly. The respondents applied to strike out the claim, including on the basis that no causative link to their actions could be established given that climate change is the product of emissions from millions of sources, located globally, over many decades.4
The Supreme Court of New Zealand refused to strike out the claim. It relevantly concluded that the question of causation of climate-related harm could only be determined following trial, with the benefit of evidence as to the scientific attribution of climate change to the respondents' activities.5 The matter has been remitted for trial. (See our briefing for further information.)
Similarly, in Shell v Milieudefensie (see our briefing) the Hague Court of Appeal concluded that Shell had a private law obligation to take measures to counter climate change, given its status as a major contributor to scope 3 GHG emissions and the likely impact of those emissions on the Netherlands.6 However, it did not uphold a lower court ruling requiring Shell to reduce its scope 3 GHG emissions by 45% (or any other specified percentage).
