As the physical impacts of climate change accelerate, so too has a parallel phenomenon: a dramatic global surge in climate change litigation. Once a niche area of environmental law, climate lawsuits are now proliferating across continents, transforming courtrooms into critical arenas where governments and corporations are increasingly being held accountable for their actions—or inactions—on global warming. This isn't just about seeking damages; it's about compelling systemic change, pushing for stronger climate policies, and defining the legal boundaries of environmental responsibility.

Why does this matter now? Because these legal challenges are not merely symbolic. They are shaping national climate policy, forcing companies to disclose climate risks, and setting powerful precedents that could redefine global efforts to mitigate and adapt to a changing climate. The outcomes of these cases have tangible consequences for economies, industries, and the lives of millions.

A Rapidly Expanding Legal Landscape

Over the past decade, climate litigation has moved from the fringes to the mainstream of climate action. According to reports from the United Nations Environment Programme (UNEP) and Columbia University's Sabin Center for Climate Change Law, the cumulative number of climate change-related cases filed globally more than doubled between 2017 and 2023. As of late 2023, over 2,500 such cases have been filed across 65 jurisdictions, indicating a significant and sustained increase in legal challenges aimed at addressing climate change.

This growth reflects several factors:

• Increasing Urgency: Public awareness of climate impacts is growing, fueling demands for action.
• Legal Innovation: Lawyers are developing novel legal theories to link climate change to existing laws, such as human rights, consumer protection, and corporate fiduciary duties.
• Data Availability: Improved climate science and attribution studies provide stronger evidence linking emissions to specific impacts.

Who is Being Sued, and Why?

Climate lawsuits generally fall into two broad categories: those targeting governments and those targeting corporations.

Governments Under Scrutiny

Governments are increasingly sued for insufficient climate action – for not meeting their own emissions reduction targets, or for failing to protect citizens from climate impacts.

• Human Rights Arguments: A common approach asserts that inadequate climate policy violates fundamental human rights, such as the right to life, health, or a healthy environment.
• Public Trust Doctrine: Some cases argue that governments have a fiduciary duty to protect shared natural resources for future generations.

A landmark example is the 2019 Urgenda Foundation v. State of the Netherlands case, where the Dutch Supreme Court ordered the government to cut emissions by at least 25% by 2020 (compared to 1990 levels), citing human rights obligations. This case set a global precedent, demonstrating that courts could mandate specific climate action from states.

More recently, in April 2024, the European Court of Human Rights ruled in Verein KlimaSeniorinnen Schweiz and Others v. Switzerland that Switzerland had violated the human rights of its elderly citizens by failing to adequately tackle climate change. This historic ruling established a clear link between climate inaction and human rights violations, setting a powerful precedent for future cases across Europe and beyond.

Corporations in the Crosshairs

Corporations, particularly those in the fossil fuel industry, face litigation on multiple fronts:

• Deception and Misinformation: Accusations that companies knowingly downplayed climate risks or misled the public about the environmental impact of their products.
• Failure to Adapt: Claims that companies failed to adequately prepare for climate change impacts, leading to damages.
• Fiduciary Duty: Lawsuits by shareholders arguing that company boards failed to manage climate-related financial risks.
• Greenwashing: Claims that companies are falsely marketing themselves as environmentally friendly without substantive action.

Major oil and gas companies have faced lawsuits from cities and states seeking damages for climate change impacts like sea-level rise and extreme weather events, arguing that these companies should bear the costs of adaptation given their historical contribution to emissions. While many of these are ongoing, they represent a significant legal and reputational threat.

Diverse Legal Strategies and Landmark Victories

The innovative legal strategies employed by climate litigants are truly diverse, reflecting the multifaceted nature of climate change itself.

Notable Approaches:

• Constitutional Cases: Directly challenging government policies based on constitutional rights.
• Administrative Law: Reviewing decisions by regulatory bodies related to fossil fuel projects or environmental permits.
• Tort Law: Seeking damages for harm caused by climate change (e.g., nuisance, negligence).
• Consumer Protection: Targeting misleading environmental claims.

Beyond Urgenda and KlimaSeniorinnen, other significant cases include:

• Milieudefensie et al. v. Royal Dutch Shell (Netherlands, 2021): A Dutch court ordered Shell to cut its global CO2 emissions by 45% by 2030 (compared to 2019 levels), marking the first time a court held a corporation legally responsible for its contribution to climate change.
• Youth v. Montana (USA, 2023): Young plaintiffs successfully argued that Montana's fossil fuel-friendly policies violated their constitutional right to a clean and healthful environment, a first-of-its-kind victory in the U.S.
• Luciano Lliuya v. RWE AG (Germany, ongoing): A Peruvian farmer is suing German energy giant RWE for its share of climate impacts (glacial melt and flood risk) in his hometown, based on the polluter pays principle. This case, though not yet decided, represents a significant transnational climate liability claim.

These victories, while often country-specific, send powerful signals globally, inspiring similar actions and reinforcing the idea that climate change is a legal issue, not just an environmental or political one.

Challenges and Limitations

Despite the growing success rate, climate litigation is not without its challenges.

• Causation: Proving a direct causal link between a specific entity's emissions and a specific climate impact can be scientifically and legally complex.
• "Floodgates" Concerns: Courts may be wary of opening the door to an overwhelming number of similar lawsuits.
• Political Interference: Governments and powerful corporations can exert significant influence, including through legislative changes or extensive legal battles.
• Enforcement: Even with a favorable ruling, ensuring compliance can be difficult, particularly for systemic changes.
• Funding: Litigation is expensive and time-consuming, posing a barrier for smaller organizations or individuals.

What This Means for Policy and Business

The proliferation of climate litigation is forcing a re-evaluation of responsibilities and risks for both public and private sectors.

For Governments:

• Heightened Pressure: Courts are increasingly holding states to their climate commitments, potentially compelling more ambitious Nationally Determined Contributions (NDCs) under the Paris Agreement.
• Policy Adjustment: Governments may be forced to revise laws, regulations, and investment strategies to align with climate goals and avoid legal challenges.
• Increased Transparency: Litigants often demand data and documents, leading to greater governmental transparency on climate-related decision-making.

For Businesses:

• Growing Financial Risk: Lawsuits can lead to significant damages, legal fees, and reputational harm. Climate liability is becoming a material financial risk that investors are increasingly considering.
• Shift in Investment: Companies, particularly those in high-emitting sectors, may face pressure to divest from fossil fuels and accelerate their transition to cleaner operations.
• Enhanced Disclosure: Expect greater scrutiny and demands for transparent reporting on climate risks, emissions, and transition plans. Greenwashing claims will likely intensify.
• Supply Chain Impacts: Litigation could extend to supply chains, holding companies accountable for the emissions generated by their suppliers.

In essence, climate litigation is adding a powerful, new layer of accountability to the climate crisis. It's a testament to the growing realization that while political will is crucial, legal action can serve as a vital catalyst, driving change where policy and market forces alone might falter. The courtroom has become an indispensable arena in the urgent fight for a sustainable future.