The Global Rise of Climate Litigation

The latest United Nations Environment Programme report charts the continued growth of climate litigation worldwide and the widening range of issues now reaching courts.

Climate change is increasingly shaping court dockets worldwide, with 3,099 climate-related cases filed across 55 national jurisdictions and 24 international or regional bodies as of June 30, 2025. The disputes now reaching courts span nearly every corner of climate governance, from emissions targets and adaptation failures to corporate conduct and climate-related financial claims.

These conclusions, from the latest United Nations Environment Programme (UNEP) report, “Climate Change in the Courtroom: Trends, Impacts and Emerging Lessons,” suggest that judges are being called to decide complex climate-related disputes over who must act, who should pay, and what the law requires when a party claims climate harms are severe.

The report is the fourth in a UNEP series launched in 2017 and draws on Columbia Law School’s Sabin Center for Climate Change Law’s Climate Litigation Database. In addition to tracing the growth of climate litigation worldwide, the report is also notable for its clarity and organization, offering a highly readable overview of a field that has become both broader and more complex.

The Numbers

In 2017, 884 climate cases were recorded. Just three years later, in 2020, that number had nearly doubled to 1,550. By mid-2025, cases had doubled again to 3,099.

One of the report’s most striking findings is the degree to which the United States continues to dominate the climate litigation landscape: Nearly 65% of tracked cases originated there, with the remainder spread across all other jurisdictions combined. Four countries besides the United States — Australia, Brazil, Germany, and the United Kingdom — have each seen more than 51 climate cases each.

Outside the United States, the report identifies 611 cases in countries in the Global North, 305 in countries in the Global South, and 216 before international or regional courts, tribunals, quasi-judicial bodies, or other adjudicatory bodies. UNEP notes that the term “Global South” is contested, but the figures still provide a sense of the distribution of climate litigation worldwide. Notably, although the Global South still accounts for less than 10 percent of tracked cases, its share is rising steadily.

UNEP cautions against reading the numbers too rigidly. The database is not exhaustive, and some cases are added only after a decision is issued rather than when a claim is first filed. A lower number in any given year, therefore, does not necessarily mean climate litigation is declining.

The Expanding Scope of Climate Litigation

Just as notable as the rise in filings is the breadth of issues now reaching courts. According to the report, climate litigation reaches into almost every corner of climate governance. Courts are being asked to decide cases about government climate targets, fossil fuel production, adaptation failures, carbon sinks, climate migration, corporate emissions, financial-sector responsibility, climate disclosures, carbon offsets, and greenwashing.

The report also identifies the rise of anti-climate, or backlash, litigation as an important emerging trend. These cases may aim to delay or dismantle environmental protections, challenge climate-related investment strategies, or target those opposing high-emitting projects. The report also noted an increase in lawsuits against climate advocates, including protesters, journalists, and civil society groups.

This growing mix of claims has made the courtroom a site not only of accountability, but also of conflict over the direction of climate policy itself.

Rights, Duties, and the Judicial Role

The report identifies three broad aims behind climate cases: shaping legislation and policy, framing rights and obligations in the climate context, and seeking redress for climate harms.

In practical terms, courts are being asked some of the hardest questions in climate governance: whether governments have enforceable duties to act, whether companies can be held liable for climate-related harm, and what counts as adequate disclosure, meaningful participation, or a lawful climate target.

One of the report’s clearest themes is litigants’ growing reliance on human rights law in arguing for answers to those questions. Rights-based arguments are becoming increasingly common, moving climate litigation beyond broad moral claims and into the language of legal duty.

Recent international developments underscore that shift. The report highlights both the International Tribunal for the Law of the Sea “Advisory Opinion on Climate Change and International Law” (Case No. 31, 2024) and Advisory Opinion OC-32/25 of the Inter-American Court of Human Rights. The former found that greenhouse gas emissions can amount to marine pollution under the U.N. Convention on the Law of the Sea and confirmed states’ obligations to prevent, reduce, and control that pollution; the latter clarified that the right to a healthy climate is protected under the American Convention on Human Rights and linked that right to life, health, water, food, housing, and dignified existence.

The Limits of Litigation — and a Clear Trend

The report makes clear that courts are only one part of the broader legal and institutional response to climate change. While litigation can push institutions to act, deter backsliding, and sometimes unblock political or administrative inertia, courts do face limits. Many legal systems still require plaintiffs to show a clear, individualized, and imminent harm — a difficult test in climate cases, where damage is often cumulative and unevenly distributed.

What emerges from the report is a picture of climate litigation as broader, more varied, and more consequential than it first appears. Some cases are classic public-interest claims against governments. Others are commercial disputes over carbon markets or lawsuits over allegedly misleading environmental claims. What the report offers, above all, is a useful high-level map of a legal landscape that is growing more crowded, more varied, and more consequential.

Still, the direction is clear. Climate change is no longer only shaping diplomacy, legislation, and regulation; it is also reshaping court dockets worldwide. Judges around the world are increasingly facing some of the defining legal questions of our time.

Michelle Kaminsky is a senior editor and writer at the Bolch Judicial Institute of Duke Law School and managing editor of Judicature and Judicature International, published by the Institute.

We would welcome hearing from Judicature International readers with experience in climate litigation in their jurisdictions. Please contact judicature@law.duke.edu to share your perspective.