ALTHOUGH the International Court of Justice’s July 2025 advisory opinion on climate change was a watershed moment in climate action, it received limited attention from Pakistan’s legal and climate communities. This landmark decision by the ICJ’s 15 judges authoritatively clarifies states’ legal responsibilities, establishing the 1.5 degrees Celsius temperature threshold as the binding global benchmark. COP30 in Belém has since acknowledged growing risks of overshoot.

The court’s opinion imposes on every state a binding obligation to demonstrate its “highest possible ambition” in climate action. This requires aligning Nationally Determined Contributions and regulatory frameworks with the scientifically determined target. Significantly, the court’s analysis extends state responsibility to the full lifecycle of fossil fuels: production, licensing, subsidies, and downstream indirect emissions across the value chain. The opinion confirms that IPCC assessments constitute “the best available science”, rendering fossil fuel subsidies potentially wrongful when foreseeably incompatible with temperature limits.

The ICJ’s reasoning unfolds through five foundational principles:

Precautionary approach: Scientific uncertainty cannot justify inaction. The court emphasises that IPCC warnings mandate immediate protective steps, even as 1.5°C proves unsafe for vulnerable populations of countries like Pakistan at current 1.2°C warming.

Duty to prevent significant harm: Under customary international law, states must exercise due diligence to prevent transboundary environmental damage, extending to all anthropogenic GHG contributions from production through consumption.

Common but differentiated responsibilities and respective capabilities........

© Dawn