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Transformative Constitutionalism and Climate Litigation


Climate change through its very nature is making survival much more difficult for those most vulnerable and dependent on natural resources. It hits those countries the hardest which have contributed less to global emissions and have less resources to deal with this challenge.  Next to the known problems of climate litigation, such as problems of proof, causation, and future effects, constitutional climate litigation has also to deal with this challenge of unequal burdens. In this blog post, I argue that one such approach to deal with this challenge is transformative constitutionalism (TC). The complexity of climate litigation is pushing courts to question dominant conceptions of constitutional law.

My understanding of the concept comes from Karl Klare’s seminal essay on TC and the two decades of global scholarship that has followed. TC seeks a transformation of societies to a culture of justification, substantive equality, a commitment to social and economic rights and reflexivity. In addition, affirmative state duties, horizontal obligations, participatory governance, and historical self-consciousness are part of TC. This aspect is particularly crucial since TC through its emphasis on reflexivity and economic and social rights facilitates two important things. Firstly, it lets each court reflect on its country’s role in leading to climate change and accordingly affix responsibility in line with international climate law. Secondly, it focuses on remedies to climate injustice based on affirmative state duties.

I argue that courts can locate the transformative potential of law not only through the explicit text of a constitution (although that is one of the main drivers), but also through extra constitutional drivers such as international law. In doing so, courts are able to challenge pre-existing structures of tradition, legality and culture. I will demonstrate this through a brief analysis of key climate cases from both the Global North and the Global South, namely from the Netherlands, Pakistan, Colombia, and Germany. In addition, I also aim to show that considerations usually associated with TC can emerge in both Global North and South contexts.

Netherlands (Threshold)

In the Urgenda case a Dutch district court ordered the state to reduce emissions by 25 % until the end of 2020 (compared to 1990). After the judgment had been appealed, one of the questions the Dutch Supreme Court had to deal with was whether the threshold of a minimum commitment to 25 % reductions on emissions by Netherlands was legally binding or not. What is interesting in the Dutch case is that its Constitution does not allow for judicial review on constitutional grounds per se. However, complainants are allowed to rely on fundamental rights norms enshrined in the European Convention on Human Rights (ECHR), making the ECHR a de facto Constitution with regard to rights violations. According to established case law by the European Court of Human Rights (ECtHR), an interpretation of the ECHR must be effective and take into account the relevant rules of international law as referred to in Article 31 (3) (c) of the Vienna Convention on the Law of Treaties.

This then, was the basis used by the Dutch court to frame a positive obligation for its government to do “its part” in tackling the climate problem.

Urgenda, the NGO behind that case, argued  that the rights in Articles 2 and 8 of the European Convention on Human Rights (ECHR) were applicable since the target reduction would affect the citizens’ right to life and privacy. A preliminary hurdle that the court dealt with was the State’s argument that these two articles did not contain obligations to protect against climate change. Being of a global nature the risks were not specific enough to be covered by the ECHR. Relying on the precautionary principle, the court held that there was scientific consensus on the risks and just because some of them might become apparent merely in the future, this would not exclude ECHR protection.

The transformative part of the judgment, however, concerns the court’s determination that the obligation of the 25 % reduction target was covered under the positive obligations of Articles 2 and 8. Relying on Demir v.  Turkey decided by the European Court of Human Rights, the court held that in interpreting the ECHR, it could rely on international instruments (binding or not) as long as they ‘denote a continuous evolution in the norms and principles applied in international law or in the domestic law of the majority of member States of the Council of Europe and show, in a precise area, that there is common ground in modern societies.’ The 25 % target was based on expert opinion in a 2007 IPCC report. What, however, transformed it into common ground was the continuous endorsement by the Conference of Parties to the Paris Agreement and the EU in subsequent years. The Supreme Court thus held that there is sufficient consensus regarding the need to reduce emissions by 25-40 % for developed countries (of which 25 % was the lower point).

In line with Transformative Constitutionalism’s emphasis on a culture of justification, the court reasoned that the state needed to justify a change in its policy given the extraordinary global climate situation. And we also find another element of TC in the Court’s reasoning: the Court explicitly took into account the context set forth in the Paris agreement which requires developed countries to bear a higher share of emissions reductions in line with their historical contributions to global warming.

Pakistan (Court’s Role in Building Adaptive Capacities)

In Leghari v. Pakistan, shortly after Urgenda, the Lahore High Court held that in failing to implement a climate policy framework the State has put its citizens in danger. Accepting the plaintiff’s submission that this failure of implementation is violating the right to life under Article 9 of the Constitution, the court prescribed specific actions to be taken by the government and appointed a climate change commission to enforce implementation of a national climate plan. Akin to Urgenda, the court pushed its transformative potential by citing international law and scientific consensus on required climate actions. Citing prior cases, the court held that Pakistani environmental jurisprudence had weaved international environment principles into its constitutional values and fundamental rights. These principles were inter alia, the doctrine of public trust, sustainable development, the precautionary principle and intergenerational equity. In particular, the court stated that unlike localised environment problems like air pollution, climate change had a global dimension and hence international law in this regard was crucial to complement constitutional principles. Elaborating, the court contended that a climate justice approach would now be required with a human centric focus to deal with the uneven impacts of climate change. Being a developing country with limited resources, adaptation rather than mitigation ought to be the way forward for Pakistan and in the court’s opinion this could only be achieved through a climate just approach “where courts help build adaptive capacities and climate resilience by engaging with multiple stakeholders.” Thus, the court envisaged a transformative role for itself, to balance interests and address social aspects of the climate problem along with environmental aspects and found the justification for it in international law.

Colombia (Standing for Nature)

A petition filed by 25 youths against the Colombian state to claim their right to a healthy environment reached the Colombian Supreme Court in appeal in 2018. The plaintiffs claimed that Colombia’s inability to comply with its target of net zero deforestation in the Colombian Amazon by 2020 threatened their fundamental rights to a healthy environment, life, health, food and water. Significantly, the court declared that the Colombian Amazon was itself a “subject of rights” which was entitled to protection, conservation, maintenance and restoration. The court then ordered the government to implement plans to stop deforestation in the Amazon. The direction to treat the Amazon as a subject of rights was transformative in the sense that it not only challenged existing notions of standing but potentially set the stage for a change in the very structures of justice. By treating the Amazon as a juridical entity, the court in effect expanded access to justice, since any Colombian citizen could now approach the court on behalf of it instead of needing to prove violation of a personal right. Again, the driver for this decision was located by the court in international law. The court mentioned the country’s updated environment legislations in line with its 1991 Constitution. Specifying several articles including fundamental rights, the court claimed that an ecological public order and an ecological Constitution has been built on the foundation of these articles. Importantly, however, the court observed that numerous provisions of hard and soft law had emerged in the international sphere constituting a global ecological public order and serving as a guiding criterion for national legislations and courts when resolving citizen complaints in the sphere of environmental rights.

Germany (Future Effects)

The German Constitutional Court articulated its position on the international dimension of climate change perhaps most clearly. Understanding that the climate mandate enshrined in Article 20a of its basic law depends on international co-operation the court stated in its decision from April 2021 that there was a “constitutional necessity” to consider the international target as the relevant benchmark and the basis for constitutional review (thus overriding Section 3 of Germany’s Climate Protection Act).  The ruling’s transformative aspect came through with the court holding that although the legislator had done enough to protect the plaintiffs in the present, the Climate Protection Act did not enact provisions on emissions reductions post 2031. Ordering the State to do so by December 2022, the court reasoned that since the current plan allowed for unrestrained depletion of the carbon-budget (as long as it met certain overall targets), this could interfere with the freedom of future generations who would have to make the transition to climate neutrality much quicker thus limiting their individual freedoms. Further, relying on the doctrine of proportionality, the court held that the Climate Protection Act must be proactive and not create a situation where the burden is disproportionately placed on future generations since this “narrows remaining options for reducing emissions in compliance with Article 20a.” The amount of time remaining was a key factor in determining how far freedom protected by fundamental rights would be restricted when transitioning to a climate neutral society.


In this blog post, I have argued that a global transformation project is taking place spearheaded by Constitutional courts of various legal orders in climate litigation. As can be seen above, countries have differing approaches to the achievement of transformational change and there could be several benefits as well as criticism of each. However, a common thread runs through these judgments which identifies the climate problem as unique because of it being a global commons issue, thus requiring international law to be paramount in interpreting domestic constitutional provisions. Using this approach, courts are able to challenge pre-existing structures of tradition, legality and culture and widen the law’s transformative ambit to account for social justice aspects of climate litigation. Future scholarship on the issue could help further understand approaches to TC and how courts understand the position of their countries in terms of their contribution to and potential resolution of the climate problem.

Eklavya Vasudev

Eklavya Vasudev is a doctoral candidate in law at the Friedrich-Alexander-Universität Erlangen-Nürnberg.

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