ICJ ruling sets precedent for suing over climate change emissions

The ruling follows the previous trend where major powers have largely relied on the Paris Agreement as the primary treaty of significance. However, this agreement had gaps, as it did not enforce strict actions for each country.

This ICJ decision not only opens a legal pathway for states affected by the climate crisis but also signals that the damage caused by greenhouse gas emissions is no longer confined to political or diplomatic negotiations. 

Instead, it is now recognised as a "right and duty" under international law that can be enforced.

Yuji Iwasawa, an ICJ judge, stated that the climate crisis is an urgent threat that impacts the survival of humanity. He also emphasised that greenhouse gas emissions are "clearly the result of human activity" and are not limited to the borders of any single nation.

Pressure on major powers

The ICJ’s judgment underscored the principle that every state holds “international obligations” to avoid causing transboundary environmental harm. Should a country fail to reduce emissions and inflict damage on another, it may now face lawsuits and compensation claims.

This elevates climate disputes to the same level as border conflicts or treaty violations, potentially triggering binding international legal consequences.

Major emitters such as the United States, China and the European Union could come under heightened legal scrutiny, particularly from small island states and developing nations suffering disproportionately from intensifying natural disasters.

For instance, Pacific island nations threatened by rising sea levels could pursue claims against high-carbon economies.

Scholars argue that the legal pathway established by the ICJ will incentivise major powers to act more decisively, given the mounting risk of lawsuits and costly damages.

A legal blueprint

Joie Chowdhury, senior attorney at the Center for International Environmental Law (CIEL), hailed the ruling as a “clear legal blueprint” for holding major polluters accountable.

“This opinion will serve as persuasive authority in domestic and regional courts and could form the basis of future state-to-state litigation,” she said. “Courts worldwide already cite ICJ judgments, and it is highly likely they will use this latest opinion to interpret binding law within their jurisdictions.”

She added that if major polluters fail to adjust their conduct in line with the court’s guidance on permissible and impermissible practices, they could be sued

While jurisdictional and technical hurdles remain, Chowdhury noted that the chances of seeing such cases before the ICJ and other tribunals are now considerably higher.

Climate litigation surges worldwide

The ruling also paves the way for cases targeting “indirect emissions,” such as carbon exports, fossil fuel subsidies, or the approval of polluting projects that harm the people or territories of other nations.

Globally, more than 2,600 climate-related lawsuits have already been filed, spanning actions against governments, fossil fuel corporations, or both. These range from youth-led cases in Europe to frontline communities demanding compensation for direct climate impacts.

The ICJ further clarified that harmful climate conduct goes beyond greenhouse gas emissions alone. It also covers state policies, project approvals and subsidies that exacerbate the climate crisis.

In effect, governments may be found liable not only for what they emit, but also for what they enable or fail to regulate.