2. Procedures and Evidence

3. DEVELOPMENTS IN LEGAL ARGUMENTS AND DEFENCES

This section outlines how plaintiffs' arguments are navigating through and overcoming traditional obstacles and challenges in corporate climate litigation, including corporate defences and previous unfavourable judicial responses.

Partial and Autonomous Responsibility

Plaintiffs have made significant strides in overcoming the common corporate defences of diffuse climate responsibility, "drop in the ocean," "perfect substitution", and the political question doctrine.

Defendants often claim that responsibility for climate change is diffuse and that imposing a reduction mandate on a single entity is merely a "drop in the ocean," thus having a negligible impact on combating climate change, as highlighted in the Urgenda case. Moreover, defendants assert, as exemplified in the Shell case, that any reduction in a company's emissions would simply be negated by "perfect substitution." This phenomenon occurs when other companies increase their emissions to step in to fill the void left by those who have cut back. In addition, the defence of political question doctrine maintains that climate change issues are beyond the purview of judicial review and are best addressed by the legislative and executive branches of government. This defence contends that climate change management is beyond judicial purview and best handled by legislative and executive branches due to its complex economic, environmental, and social implications, a stance adopted in Rybnik and Łódź cases in Poland and AEP v. Connecticut in the US.

Despite these challenges, cases across various jurisdictions show a growing judicial recognition that corporations, regardless of the scale of their emissions, bear a responsibility for mitigating climate change.

In the Netherlands, the landmark rulings in the Urgenda and Shell cases have established the notion of partial and autonomous responsibility for climate harm based on national tort and human rights law.

• The Urgenda case, adjudicated by the Dutch Supreme Court, set a precedent by affirming that every reduction in emissions positively contributes to climate change mitigation. It rejected the notion that individual emitters could evade responsibility by pointing to others' inaction, emphasising that such a stance undermines legal protections against climate risks. The Supreme Court stated: "the assertion that a country's own share in global greenhouse gas emissions is very small and that reducing emissions from one's own territory makes little difference on a global scale, [cannot] be accepted as a defence. Indeed, acceptance of these defences would mean that a country could easily evade its partial responsibility by pointing out other countries or its own small share". The court also established the autonomy of this responsibility, indicating it exists independently of legislative actions and can be enforced through private law.

• Similarly, in the Shell case, the court dismissed Shell's argument that emission reduction mandates could be counterproductive, recognising instead the intrinsic value of any emission decrease. It also rejected the idea of a 'perfect substitution' by other companies, reinforcing the broader duty of corporations to protect human rights and reduce emissions.

In Germany, the RWE case represents a move toward recognising corporate responsibilities in climate change efforts, with the Higher Regional Court of Hamm showing openness to partial liability by investigating the causal link between RWE's emissions and climate impacts.

Duty of Care in Public Nuisance and Negligence Suits

Plaintiffs have navigated the hurdles of corporate defence of legal and regulatory compliance in public nuisance and negligence suits by emphasising the "duty of care" and the tangible harm caused by corporate actions on the climate. The common defendants' strategy is to assert legal compliance, where corporations argue their operations adhere to existing environmental laws and regulations. This defence not only emphasises the legality of their actions but also shifts the burden of regulatory inadequacy onto government bodies, suggesting that current legal frameworks sanction their activities. Such arguments raise critical questions about the adequacy of existing environmental regulations and the role of legislative and regulatory bodies in mitigating climate change.

The duty of care requires individuals or entities to act with reasonable care and take precautionary measures to prevent foreseeable harm. In corporate climate litigation, this means corporations must consider and mitigate their environmental impact to prevent or reduce public and environmental harm. Successful claims have highlighted corporations' failure to warn about the climate and environmental risks of their products or operations.

• Noteworthy is the German Federal Court of Justice's 1984 decision, establishing that civil law may require permit holders to implement additional safeguards if clear risks are identified, regardless of public-law compliance. Following this principle, the Regional Court of Braunschweig rejected Volkswagen's contention that compliance with public law permits and European emission standards absolved it of any additional duties. The court determined that possession of a permit or adherence to European regulations does not inherently release an entity from its responsibilities. It highlighted the fact that public law requirements and civil law obligations do not necessarily coincide or proceed alongside each other.

• In India, the Bhopal Gas Tragedy case represents a stark example of the failure to warn and protect the public from industrial risks. The Indian government represented the residents living near the Union Carbide plant, arguing that the community was not informed about the dangers of the gas or the precautions to take in the event of a leak. In 1984, a disastrous leak of methyl isocyanate gas from Union Carbide India Ltd.'s pesticide plant in Bhopal resulted in the death of approximately 1,700 people and injuries to many others. A court settlement later required the Union Carbide Corporation to pay for the damages caused. The settlement emphasised corporate responsibility for environmental harm, reinforcing the duty of care principle.

• In the Shell case in the Netherlands, Shell maintained that imposing a duty of care to mitigate climate change risks would be pointless, as any reduction in its emissions would merely be offset by increased emissions from other companies filling the gap. As discussed in Part 4(a) above, the district court dismissed Shell's argument, highlighting the overarching responsibility of corporations to reduce emissions.

Economic and Societal Considerations

Plaintiffs in corporate climate litigation have manoeuvred through the defences that highlight the potential economic consequences and societal benefits of activities (e.g., use of fossil fuels) linked to climate change.

Defendants often warn of the economic fallout from imposing strict climate change-related liabilities, suggesting such actions could harm the economy, lead to job losses, and disrupt energy supplies. They frame this argument as a dilemma between safeguarding the environment and maintaining economic stability, challenging courts to strike a delicate balance between these seemingly conflicting interests. Additionally, defendants underscore the societal gains from the use of fossil fuels and other activities that emit greenhouse gases, arguing that these are indispensable to the fabric of modern society and contribute significantly to overall welfare.

• In the United States, defendants in public nuisance cases have used the balancing test to defend the reasonableness of their actions, articulated as follows: "if the harm resulting from the invasion is severe and greater than the other should be required to bear without compensation" (Restatement 2d of Torts, Section 829A). They argue the societal benefits of fossil fuels against the plaintiffs' own usage of these resources, posing a significant challenge for plaintiffs to overcome (City of New York v. Chevron Corp.).

This line of defence forces plaintiffs to demonstrate the social unacceptability of the risks associated with the practices deeply woven into our societal and economic structures, which utilise dependence on fossil fuels as a shield against liability.

• In 2021, the Mito District Court in Japan issued an injunction to cease the operation of a nuclear power plant, siding with plaintiffs who contended that the societal unacceptability of the risks——understood as the combination of the potential damage and the likelihood of its occurrence—justified shutting down the plant.

Causation and Attribution Science

Defendants often highlight the inherent difficulty in establishing a direct causal link between their emissions and specific climate change impacts, citing the global, diffuse nature of greenhouse gas emissions and the complex interplay of factors contributing to climate change. Expanding on this issue, Section 2.D on Sources of Evidence and Procedure Related to Causation discusses how attribution science is applied in corporate climate litigation to establish a direct link between corporate activities and climate change impacts.