WYCJ Symposium: Climate Change Litigation – Stepping Stones Towards an International Court of Justice Advisory Opinion

Introduction

Climate change litigation has become an increasingly important tool in efforts to address the climate crisis. Where legislative and diplomatic progress has often been slow, individuals, NGOs, communities, and subnational governments have increasingly turned to courts and tribunals.

This article considers how that growing body of litigation could help shape a future advisory opinion from International Court of Justice on states’ obligations concerning climate change. It identifies two major trends in climate litigation:

• a rights-based approach

• a focus on intergenerational equity

These developments, the author argues, could act as stepping stones toward an influential ICJ advisory opinion.

Climate Litigation as Legal Mobilisation

Climate litigation refers broadly to using legal processes before courts or tribunals in a climate-related context. It has expanded globally because formal climate governance has often struggled to deliver sufficiently ambitious action.

Litigation can:

• pressure governments to strengthen policy

• clarify legal obligations

• interpret constitutional and human rights guarantees

• hold public and private actors accountable

However, litigation is still case-specific and reactive. It cannot substitute for comprehensive legislation or international treaty-making.

Rights-Based Climate Litigation

A major recent development has been linking climate change to human rights. Courts increasingly recognise that climate harms threaten rights such as:

• life

• health

• housing

• family life

• dignity

• equality

This “rights turn” gives climate claims stronger legal footing and frames climate change as a human issue rather than merely an environmental one.

Key Domestic Cases

Leghari v Pakistan

The Lahore High Court held that climate change was a defining challenge of the time and that state inaction could violate citizens’ fundamental rights. It emphasised climate justice.

Urgenda Foundation v The Netherlands

This landmark Dutch case found that inadequate emissions reductions could breach duties linked to the rights to life and private life. The court required the state to meet stronger emissions targets.

This decision became globally influential because it showed courts could order concrete climate action.

International Human Rights Developments

Regional and international bodies have also strengthened the connection between human rights and climate change.

Inter-American Court of Human Rights

Its advisory opinion on environment and human rights recognised that a healthy environment is necessary for the enjoyment of many rights.

Inter-American Commission on Human Rights

Its Climate Emergency Resolution identified climate change as a major threat to human rights.

Committee on the Rights of the Child

In Sacchi et al v Argentina et al, the Committee acknowledged that failures to take preventive climate measures may implicate children’s rights.

Intergenerational Equity

The second major trend is the growing role of intergenerational equity—the principle that current generations must not exhaust or irreparably damage environmental resources needed by future generations.

In climate terms, this means present policy choices should not impose unfair burdens on younger people and those yet to be born.

Important Cases on Future Generations

Oposa v Philippines

The Supreme Court of the Philippines recognised that environmental rights extend to future generations.

Shrestha v Nepal

The Supreme Court of Nepal linked intergenerational equity to climate justice.

Neubauer et al v Germany

The Federal Constitutional Court of Germany ruled that insufficient action today could force drastic restrictions on freedoms tomorrow, effectively making intergenerational fairness judicially enforceable.

Why This Matters for the ICJ

The International Court of Justice is not formally bound by precedent in the same way many domestic courts are. It does not have to follow other tribunals’ decisions.

However, international courts often engage in cross-fertilisation—drawing on reasoning from other jurisdictions.

That means the ICJ could consider:

• national constitutional climate rulings

• regional human rights decisions

• UN treaty body reasoning

• broader trends in international law

Especially persuasive would be decisions reflecting wider international consensus rather than isolated national judgments.

Potential Value of an ICJ Advisory Opinion

A strong advisory opinion could clarify states’ obligations under international law regarding:

• emissions reduction

• prevention of transboundary harm

• protection of human rights from climate impacts

• duties owed to children and future generations

• international cooperation and equity

Although advisory opinions are formally non-binding, they can carry major legal and political authority.

Conclusion

The article argues that recent climate litigation has already laid the groundwork for an eventual ICJ advisory opinion. Courts around the world are increasingly recognising two core ideas:

1. climate change is a human rights issue

2. states owe duties to future generations

These cases may not bind the ICJ, but they can help shape its reasoning. In that sense, climate litigation serves as a series of stepping stones toward a global legal statement on states’ climate responsibilities.

Lianne Baars was pursuing an LL.M. in Global Environment and Climate Change Law at University of Edinburgh.