ICJ’s Advisory Opinion on Climate Obligations

The International Court of Justice (ICJ) delivered its advisory opinion on July 23, 2025, concerning the obligations of states to reduce greenhouse gas emissions and the legal implications of failing to meet those obligations.

International Climate Justice and Obligations under Multilateral Environmental Agreements

1. Significance of the ICJ Advisory Opinion

• • Upholding the Multilateral Climate Regime
  • The ICJ reaffirmed the continued relevance of the UNFCCC, Kyoto Protocol, and Paris Agreement.
  • It explicitly rejected the global North’s view that the Paris Agreement alone constitutes the binding framework.
  • Acknowledged the Annex I and II distinctions under UNFCCC, reaffirming differentiated obligations for developed countries.

2. Support for the Global South

• Reaffirmation of Common But Differentiated Responsibilities (CBDR-RC)
  • Declared CBDR-RC as the core guiding principle in interpreting international climate obligations.
  • Para 152 notes its universal applicability, even beyond climate law (e.g., biodiversity).
• Recognition of Historical Responsibility
  • Maintains that obligations stem from cumulative emissions, justifying enhanced duties for developed nations.

3. Concerns Over Temperature Goal Interpretation

• Shift in Interpreting Paris Goals
  • ICJ interprets the 5°C threshold as the binding target, despite Article 2.1 of the Paris Agreement allowing a range (well below 2°C).
  • Court relied on COP decisions (e.g., COP26, COP28) to revise this threshold, which is not formally part of the treaty text.
• Critique of Methodology
  • The Court selectively cites IPCC’s AR6 emission targets (e.g., 43% cut by 2030), ignoring issues of equity and carbon space needed by developing countries.

4. On Legal Enforcement of Climate Obligations

• Nature of Obligations
  • ICJ classifies most commitments as obligations of conduct, not obligations of result.
    • For instance: Timely submission of NDCs is enforceable, while meeting targets remains discretionary.
• Gaps in Enforcement Mechanisms
  • The opinion does not establish strong enforcement pathways, depending instead on jurisdictional courts and context-specific legal battles.

5. Shortcomings in Addressing Development Needs

• Inadequate Focus on Climate Justice
  • The opinion sidelines key developmental imperatives of the Global South, such as:
    • Access to carbon space
    • Access to finance and technology for low-carbon development
  • Ignores the right to development, as noted by dissenting judge Xue Hanqin.
• Equity and CBDR as Interpretative, Not Prescriptive
  • Equity is framed only as a guiding tool, not a legally enforceable principle, raising concern for developing nations relying on it for climate negotiations.

6. Future Litigation and Implications

• Opens limited room for litigation by vulnerable states, especially Small Island Developing States (SIDS), for reparations.
• However, requires high thresholds of causation, attribution, and proof of harm.