Copyright Project Syndicate
BERLIN/BONN – Amid rising geopolitical tensions, pressure to comply with climate obligations increasingly comes from courts. Earlier this year, both the International Court of Justice (ICJ) and the Inter-American Court of Human Rights (IACtHR) issued landmark advisory opinions affirming that countries must address climate change, and that failure to do so may carry serious legal consequences. This renewed legal clarity comes at a critical moment. Last year was the hottest on record, with global average temperatures exceeding 1.5° Celsius above pre-industrial levels, yet the gulf between the urgency of the climate threat and the policy response continues to widen. In the absence of political will, the legal system has become a key driver of climate progress. As the United Nations Climate Change Conference in Brazil (COP30) approaches, the groundwork has been laid for stronger, fairer, and more accountable climate action. The task now is for governments to adapt their policies in accordance with both international law and environmental needs. The most immediate implication of the ICJ and IACtHR opinions is that national climate plans – known as Nationally Determined Contributions (NDCs) – must reflect the “highest possible ambition” and be consistent with the 2015 Paris climate agreement’s goal of limiting global warming to 1.5°C. Alarmingly, as of 2024, global temperatures are on track to rise by up to 3.1°C by the end of the century. Following the September deadline for new NDCs, only half of greenhouse-gas (GHG) emissions are covered by updated climate pledges, most of which fall well short of science-based targets. The ICJ and IACtHR decisions, however, offer some cause for hope. At COP30, negotiators and civil-society representatives can push for ambitious measures, as noncompliance with the Paris agreement’s temperature goals can be challenged not only in diplomatic forums but also in courts. A rapid phaseout of coal, oil, and gas remains essential to effective climate action. But despite the so-called “UAE consensus” to move away from fossil fuels, many countries continue to obstruct progress. Here, too, the ICJ provides negotiators with new tools, explicitly recognizing that governments may be held liable for failure to reduce GHG emissions, including through fossil-fuel production, consumption, exploration, and subsidies. The international climate regime must evolve to reflect these changing legal realities. That requires creating stronger compliance mechanisms that ensure countries meet their targets and deliver on climate-finance commitments. The legal shift is particularly evident in climate finance. For decades, developed countries have treated funding for climate adaptation and loss and damage as discretionary. Consequently, despite the establishment of the Fund for Responding to Loss and Damage at COP28, contributions remain far below what is needed. The path forward is clear. The ICJ’s opinion affirms that wealthy countries have a legally binding duty to support mitigation, adaptation, and loss and damage efforts across the developing world. To meet these obligations, at least $1.3 trillion must be mobilized annually by 2035, with dedicated provisions for loss and damage. Crucially, the private sector is not being let off the hook. The ICJ, IACtHR, and the International Tribunal for the Law of the Sea have all recognized that governments must regulate corporations where necessary to protect the environment, safeguard the climate system, and uphold human rights. At the same time, corporate accountability is taking shape in domestic courts. In a landmark decision, Germany’s Higher Regional Court of Hamm ruled that large emitters can, in principle, be held liable for climate-related impacts. The case, brought by Peruvian farmer Saúl Luciano Lliuya, shows that individuals on the front lines of the climate crisis can force polluters to pay their fair share. But litigation alone cannot deliver justice at scale. Governments must establish clear legal frameworks to hold major emitters fully accountable for their role in driving the climate crisis before the damage becomes irreversible. Mechanisms such as mandatory reserves, disclosure rules, insurance schemes, and compensation funds can help internalize liability risks and embed accountability into the system, rather than leaving it to goodwill or the courts. The momentum for such measures is building. In countries like the Philippines and Pakistan, as well as US states such as Vermont and New York, lawmakers are advancing “polluter pays” legislation. Remarkably, climate lawsuits, by plaintiffs ranging from indigenous groups in Canada to farmers in Korea, are already invoking the ICJ’s reasoning, and a Brazilian court explicitly cited it when ordering a fossil project to cease operations. Instead of waiting for the next court ruling, governments should now take steps to uphold the rule of law and assume responsibility for confronting the climate crisis. That means charting a credible path toward drastic emission cuts, accelerating the phaseout of fossil fuels, and ensuring that climate finance is effective, equitable, and fit for purpose. At COP30, international policymakers should harness the current legal momentum by proposing a global levy on fossil-fuel profits and high-emitting sectors, including shipping and aviation, to ensure sustainable financing of the Adaptation Fund and the Loss and Damage Fund.
