What does the European Court of Human Rights’ KlimaSeniorinnen Judgment Mean for Future Generations? Some Quick Reflections

Portrait of Katalin Sulyok
Katalin Sulyok (PHD)

Guest Post by Katalin Sulyok (Dr Sulyok served as a legal advisor to ENNHRI, the European Network of National Human Rights Institutions, which was an oral intervener supporting the applicants in KlimaSeniorinnen and Duarte before the Grand Chamber)

Mark your diary now for Dr Sulyok’s NZCEL Future Generation Series Keynote Lecture at the University of Auckland on Thursday 19th September 2024, details to follow.


On 9 April 2024, the European Court of Human Rights (ECtHR or the Court) in Strasbourg released three highly-anticipated climate judgments: the Duarte Agostinho and Others v Portugal and Others case, filed by six Portuguese children against 32 States; the Carême v France case, initiated by a former mayor of a coastal town in France; and the KlimaSeniorinnen v Switzerland case. This last proceeding was brought by four senior women together with an NGO comprising more than 2000 elderly women from Switzerland, who claimed a violation of their right to life, right to private life, and right to fair hearing due to the State’s lack of climate mitigation measures. While Carême and Duarte Agostinho were found inadmissible on procedural grounds, the KlimaSeniorinnen case has led the Court to issue a remarkable 230-page-long judgment which breaks new ground in many respects and marks a considerable departure from the Court’s previous environmental case-law in important ways.

A first wave of immediate scholarly reaction has already commented on various procedural and substantive aspects of the judgment (see e.g. here and here). This piece has a narrower focus and explores the ways in which the ECtHR provides protection for future generations. Specifically, this short commentary will bring out three aspects of the judgment relevant for the judicialization of intergenerational equity, namely, 1) the significance of the newly coined concept of ‘intergenerational burden-sharing’, 2) the role that climate science and policy play in the Court’s protection of future generations, 3) the content of the “right to effective protection against adverse effects of climate change”, and in addition 4) certain issues on which the ECtHR remains noticeably silent.

These remarks are made solely in my academic capacity and are fundamentally shaped by the fears and hopes held throughout the proceedings as to the possible outcomes of the case, being well-aware of the limitations of the ECtHR’s previous environmental case-law, its often vague and superficial treatment of scientific evidence, and its tendency to outline positive obligations only with very broad brushstrokes.

1) Intergenerational burden-sharing as a principle of human rights protection in Europe

Future generations, and concerns for intergenerational equity, enjoy a privileged position in the Court’s KlimaSeniorinnen judgment. Tellingly, this is the very first factor the Court mentions among the preliminary considerations informing its decision (§410). Curiously, the Court coins a new formulation, that of “intergenerational burden-sharing” (§ 410), instead of using the widely used term of “inter-generational equity” which is a recognized principle of international law featured in several sources of international law that are reiterated in the judgment itself. Even so, the Court chose to use its own formulation, echoing the March 2021 Neubauer decision of the German Federal Constitutional Court, which found that present generations must not “unilaterally offload” the greenhouse gas “reduction burden” onto future generations (§183 of Neubauer decision). By affirming the applicants’ and interveners’ pleadings invoking inter-generational equity, the ECtHR has joined a growing line of climate judgments where courts have read intergenerational equity into well-established norms. (Several such decisions are also overviewed in the judgment in a section on “Comparative Law” in §§ 232-272).

Importantly, invoking intergenerational burden-sharing is more than a rhetorical gesture, as the Court goes on to discern some concrete legal requirements from the concept. The judgment declares that “to avoid a disproportionate burden on future generations, immediate action needs to be taken and adequate intermediate reduction goals must be set for the period leading to net neutrality.”(§ 549) Intergenerational burden-sharing thus allows the Court to draw on the interplay between different timescales to enhance the duties of present stakeholders. Simply put, using the future generations narrative enables the Court to justify mandating immediate GHG cuts in the present, and thereby to prompt States to take responsibility for tackling dangerous climate change that has been partly caused by their past emissions.

Such reasoning illustrates good judicial practice for how (international or domestic) courts could factor future generations into their assessments. The added value of referring to future questions is also a key question in the currently pending advisory proceedings before the ICJ and IACtHR. The underlying questions ask these fora to clarify the legal implications of future generations for the content of States’ climate change related obligations under customary international environmental law and international human rights law. The ECtHR’s reasoning in KlimaSeniorinnen shows how future generations could be mobilized as a legal qualifier of States’ preventive due diligence obligations to ratcheting up the expected level of ambition from States under various legal contexts, in the present case, under the positive obligations flowing from Article 8 of ECHR (the right to private life).

2) Science, policy, and the Court: mainstreaming basic scientific knowledge and climate litigation standards across Europe

Intergenerational equity is often viewed by States as a non-justiciable and non-binding principle (see respondent’s position in §364). The courts may be reluctant to intervene to protect long-term assets in the climate arena, which they may view as a question of policy reserved for the legislature/executive. It is therefore significant that the judgment sets out a common foundation for climate litigation (and the protection of a safe climate for the future) across Europe by announcing some key minimum standards concerning the mechanisms of climate change, on the one hand, and the scope of the judicial task and the extent of states’ responsibility, on the other hand.

As to the phenomenon of climate change, the Court accepts certain basic knowledge “as a matter of fact” (§436) for the purposes of its own assessment. These findings emerge as undisputable shared understandings of the reality of climate change from the perspective of human rights adjudication which cannot be questioned even by domestic courts hearing climate lawsuits:

“that anthropogenic climate change exists, that it poses a serious current and future threat to the enjoyment of human rights guaranteed under the Convention, that States are aware of it and capable of taking measures to effectively address it, that the relevant risks are projected to be lower if the rise in temperature is limited to1.50C above pre-industrial levels and if action is taken urgently, and that current global mitigation efforts are not sufficient to meet the latter target.”(§436)

The Court also debunks certain ‘myths’ that keep resurfacing in climate lawsuits in the position of respondents, such as the non-justiciability of issues of climate policy, or the ‘drop in the ocean’ argument, precluding the responsibility of individual States for abating the global phenomenon of climate change (§444). The Court voices a firm view that the separation of powers doctrine does not bar its jurisdiction, as climate change, which impairs human rights “is no longer merely an issue of politics or policy but also a matter of law” (§450). On the drop in the ocean argument, the Court reaffirms that “the Convention requires that each Contracting State undertake measures for the substantial and progressive reduction of their respective GHG emission levels, with a view to reaching net neutrality within, in principle, the next three decades.” (§548)

3) The content of the ‘right to effective protection against adverse effects of climate change’

The Court summarized the essence of the protection that Article 8 (the right to private life) offers against climate change as “a right for individuals to effective protection by the State authorities from serious adverse effects of climate change on their life, health, well-being and quality of life.” (§519). I will address four aspects of the scope of protection afforded by such a right.

Mitigation vs adaptation
The Court stresses in the context of the claim before it that mitigation has priority over adaptation under Article 8, as adaptation is also required, but only as “ancillary” (§555) measures “supplement(ing)” (§552) GHG reductions measures. This is important considering that the Court could have followed in the footsteps of the UN Human Rights Committee, which in its views of September 2023 in the Torres Strait Islanders’ case found only that Australia had violated the ICCPR through the absence of adaptation measures rather than through lack of ambitious mitigation measures. The ECtHR has set the priorities straight in this regard, which was an aspect ENNRHI also emphasized in its oral and written interventions.

Standing of individuals vs NGOs
The KlimaSeniorinnen judgment also clearly marks the emancipation of climate protection from environmental protection with regard to the Court’s jurisprudence. In the Court’s view, it was “neither adequate nor appropriate” to follow its environmental case-law on standing and instead it developed “a more appropriate and tailored approach” (§421) towards climate complaints. The new approach is marked by an “especially high” (§488) threshold for individuals for claiming standing (victim status), which is, however, offset by lowering the bar with respect to standing for competent NGOs (§502).

Unlike in previous environmental disputes before the ECtHR, individuals will only have standing in climate cases if they are “personally and directly” affected by the failure of the State to protect their rights (§487). This threshold is only met if a) the applicant is subject to “a high intensity of exposure to adverse effects of climate change”, where the adverse consequences of the governmental action or inaction is significant, and b) “there is a pressing need to ensure the applicant’s individual protection”, due to the absence of any reasonable measures to reduce harm (§487).

States’ discretion
The margin of appreciation doctrine has been a central feature of the ECtHR’s case-law, which grants wide discretion to State in designing their domestic policies and has previously prompted the Court to find a violation of Article 8 only in cases involving most egregious environmental pollution. Scholars have suggested various ways of overcoming this obstacle in climate cases (e.g. Minnerop, 2019), but the Court took another path. It explicitly turned the margin of appreciation into a two-tier concept, with States having only a “reduced margin” in setting their climate targets and objectives considering their international commitments to fight climate change. As to the choice of means to implement these targets and objectives, States are still endowed with an emphatically ‘wide’ discretion (§543).

Detailed list of positive obligations
The wide margin granted to States as to their choice of measures notwithstanding, the Court offers an unusually hands-on approach to concretizing the requirements that domestic climate mitigation measures must meet in order to comply with Article 8. Notably, positive obligations have been one of the most enigmatic legal constructs in human rights adjudication, and judging by the level of detail offered by the Court to describe States’ positive obligations in previous cases, there was a real possibility that the Court would not go into such depth as regards the mandated criteria. Viewed from this perspective, it is all the more remarkable that paragraph 550 (and the accompanying sections) of the judgment mandates a complex set of State obligations by directly touching upon technical issues of climate policy-making. These requirements are worthy of being cited in full here:

“When assessing whether a State has remained within its margin of appreciation (see paragraph 543 above), the Court will examine whether the competent domestic authorities, be it at the legislative, executive or judicial level, have had due regard to the need to:
(a) adopt general measures specifying a target timeline for achieving carbon neutrality and the overall remaining carbon budget for the same time frame, or another equivalent method of quantification of future GHG emissions, in line with the overarching goal for national and/or global climate-change mitigation commitments;
(b) set out intermediate GHG emissions reduction targets and pathways (by sector or other relevant methodologies) that are deemed capable, in principle, of meeting the overall national GHG reduction goals within the relevant time frames undertaken in national policies;
(c) provide evidence showing whether they have duly complied, or are in the process of complying, with the relevant GHG reduction targets (see subparagraphs (a)-(b) above);
(d) keep the relevant GHG reduction targets updated with due diligence, and based on the best available evidence; and
(e) act in good time and in an appropriate and consistent manner when devising and implementing the relevant legislation and measures.”

The Court also adds that States should undertake “substantial and progressive reduction of their respective GHG levels, with a view to reaching net neutrality within, in principle, the next three decades” (§548). These measures must be “capable of mitigating the existing and potentially irreversible, future effects of climate change’ (§545) and be aimed at “preventing a rise in global average temperature beyond levels capable of producing serious adverse effects.” (§546) Though the Court does not unequivocally mandate States to pursue 1.50C as a temperature goal, it recognises that climate risks will be lower if warming is limited to1.50C (§436). Arguably, reading these together provides that States ought to adopt a pathway that is consistent with 1.50C warming.

Moreover, domestic mitigation measures must:
- be specified in a “binding regulatory framework at the national level”, containing the reduction targets and timetables (§549), which is effectively implemented (§ 538);
- set forth immediate reduction cuts (§549);
- be accompanied by procedural safeguards enabling public scrutiny of mitigation targets (§554), e.g. relevant information held by the state must be made available to the public, and there must be avenues for public participation especially of the most vulnerable to climate impacts;
- be complemented by adaptation measures in accordance with best available evidence and consistent with States’ positive obligations (§552).

This extended list of requirements neatly maps the most typical flaws and shortcomings in domestic climate laws and policies that have been challenged in recent climate lawsuits in various jurisdictions. Some national climate laws in Europe are still vague and/or not strictly implemented, and interim targets often fall short of the level of ambition advocated by scientists.

The Court stressed that failure to meet any one of the above criteria would not automatically trigger a violation of the Convention, as the Court will conduct an overall assessment of domestic climate measures (§551). Yet, tellingly, even such a lenient margin of appreciation was exceeded by Switzerland in the material case. What is more, several other States might fail scrutiny under this rubric considering the marked gap between the climate pledges that exist on paper and their actual implementation. Even the 55% mitigation target of the European Union falls short of what is warranted by the best available science to meet the 1.50C long-term temperature goal, according to NGOs’ submissions to the European Commission.

4) What did the ECtHR remain silent on?

Finally, I will flag some important issues and principles that were pleaded before the ECtHR by the plaintiffs and interveners, which, however, are conspicuously not featured in the judgment.

First, the precautionary principle is missing from the mandated elements of domestic climate laws, even though the principle has in the past been found by the Court to be applicable under the Convention, at least in the context of environmental impact assessment procedures (see Tatar v Romania case).

Second, and related to the lack of precautionary reasoning, the Court also did not touch upon the issue of negative emissions technologies. The interveners pointed out that the precautionary principle precludes States from relying primarily on risky and still unknown negative emission technologies in their efforts to meet net zero pledges. By not setting any requirement in this respect, the judgment appears to leave this issue for States.

Third, the judgment noticeably did not use the language of “fair shares” employed by the plaintiffs and several interveners, mimicking the approach and the well-known wording of the Dutch Supreme Court in the Urgenda case. Instead, the Court opined that “each State has its own share of responsibilities to take measures to tackle climate change and that the taking of those measures is determined by the State’s own capabilities rather than by any specific action (or omission) of any other State” (§442). Several reasons might have prompted the Court to do so, one of them being not wanting to copy any one national jurisdiction’s approach to the interpretation of Article 8 of the ECHR; another being a desire to avoid touching upon the sensitive and multifaceted issue of how to apportion the global carbon budget among several States, an issue which was hotly contested by the States also in the Duarte hearing. The ECtHR hence emphatically leaves the issue of defining national carbon budgets to States.

5) Concluding remarks on the way forward

In sum, I believe that the Strasbourg Court lived up to the legally disruptive (Fisher et al., 2017) challenge posed by climate change. This judgment has the potential to become an effective tool for climate litigants at the domestic level. Even though the KlimaSeniorinnen decision is only binding on Switzerland, given that the Court follows a consistent practice the requirements set in the judgment are a clear blueprint for other Council of Europe Member States too, when it comes to devising domestic mitigation and adaptation measures.

The Court has sent a clear signal that plaintiffs should first seek a remedy at the domestic level against unambitious or ineffective climate laws. The way forward will be marked, in the Court’s view, not by individual plaintiffs but by NGOs’ complaints. Public interest litigation has therefore received another boost to continue the fight for climate justice at the domestic level. National courts must be ready to hear challenges against unambitious or ineffective climate policies, including those highly technical lawsuits that question the appropriateness of the equity principles and calculation methods underlying a specified national carbon budget.

Importantly, the judgment does not speak to the executive and legislative powers only, but it provides a clear task also for national courts to protect future generations from majoritarian decision-making processes. The judgment explicitly cites the Venice Commission’s statement pointing out that “the judicial branch appears to be best placed to protect the future generations against the decisions of present-day politicians” (§199). In this vein, KlimaSeniorinnen visibly integrates the idea of intergenerational burden-sharing into the human rights protection system in Europe, and national courts are expected to oversee the extent and ways in which States comply with this principle in their mitigation and adaptation actions.