Two aims, among others, motivated the decision to bring the Duarte Agostinho climate case (“Duarte”) directly to the European Court of Human Rights against multiple Respondent States. They were, first, to invite the Court to interpret States’ obligations in respect of climate change in a manner capable of protecting those in the most vulnerable parts of Europe. And, second, to prompt the Court to confront the reality that the question of whether an individual State’s climate policies, and therefore the relevant remedies available in its domestic courts, are effective is an inherently relational one. In other words, climate change being a collective action problem, it is not possible to assess the adequacy of one State’s response without considering (a) what the result would be if every State were to respond in the same way and (b) what it entails for other States if we are to achieve the collective goal of avoiding its worst effects. It was thought that a regional court, with its supranational vantage point, was particularly well-placed to engage with these questions.
In light of these aims, this post addresses certain aspects of the decision of the Grand Chamber in Duarte – which dismissed the Applicants’ claim as inadmissible both because they are not within the extraterritorial jurisdiction of the Respondent States other than Portugal (the Applicants’ home State) and on the basis that they ought to have exhausted domestic remedies in Portugal – and provides a brief comment on the judgment in the related KlimaSeniorinnen climate case. Both rulings have already been discussed extensively (including here, here, here, here, here and here).
The Court’s approach to extraterritorial jurisdiction
Of particular relevance to the first aim mentioned above are the arguments advanced by the Applicants as to why, in the absence of recognition of an extraterritorial obligation, they would find themselves within a “vacuum of protection”, and the response of the Court to that argument. As noted in the Court’s decision (§125), the Applicants contended that the effective protection of their rights required recognition that they fell within the extraterritorial jurisdiction of the Respondent States other than Portugal, for the purpose of their obligation to mitigate climate change. The basis for this claim was that across Europe there is a variation in vulnerability to climate impacts and in the adaptive capacity of countries. As the IPCC has pointed out, “outhern regions tend to be more negatively affected, while some benefits have been observed, alongside negative impacts in northern and central regions”. Furthermore, “adaptive capacity […] tends to be higher in northern and western parts of Europe”, while Mediterranean countries (which, for the purpose of IPCC categorisation, include Portugal) face “hard limits” to adaption.
To demonstrate how this variation in vulnerability and adaptive capacity could leave them within a vacuum of protection, the Applicants highlighted the decision of Germany’s Federal Constitutional Court (“FCC”) in the Neubauer et al. climate case. The complainants in that case contended that Germany’s 2030 emissions target was inadequate because it was not aligned with the 1.5°C temperature limit. However, in upholding the constitutionality of the 2030 target, which the FCC found to be “possibly still oriented towards a target of 2°C”, it held that “t is not evident that the health consequences arising from 2°C global warming and from the associated climate change in Germany could not be alleviated by supplementary adaptation measures in a manner that would be sufficient under constitutional law” (§167, emphasis added).
Among the complainants in Neubauer et al. were a group of individuals from Bangladesh and Nepal. The position taken by the FCC in relation to Germany’s extraterritorial obligations towards these complainants, which is quoted in the decision in Duarte (§65), can be summarised as follows:
The thrust of the FCC’s decision is therefore that Germany can align its emissions targets with 2°C, instead of 1.5°C, because Germany has the capacity (according to the FCC) to adapt to impacts at that level of warming, while it is “the task of the states concerned” – Bangladesh and Nepal – to adopt measures to adapt to the consequences of this choice. It is hardly surprising that this position has been the subject of criticism. Glaringly absent from the FCC’s analysis was any consideration of whether the adoption by Bangladesh and Nepal of adaptation measures would even be capable of protecting their populations from the kinds of impacts they would be exposed to at 2°C. The scenes of devastation from the unprecedented flooding events that have hit South Asia in recent years, at just 1.2°C of global warming, are perhaps sufficient to answer this question.
The Applicants referred to the FCC’s decision as demonstrating how they, being residents in a particularly vulnerable European country with relatively limited adaptive capacity, could end up caught in a vacuum of protection if States’ obligations to mitigate climate change were territorially confined. However, the force of this argument diminishes when the broader existential threat of the climate crisis is kept in view. After all, if we cross the various catastrophic tipping points in the climate system (five of which we are already on the brink of), the differences between the adaptive capacities of different countries lose their relevance: by definition, no adaptation measures will protect against a scenario in which the planet ceases to be capable of sustaining human life.
It is clear from the decision in Duarte, read alongside the judgment in KlimaSeniorinnen, that the possibility of such a scenario, and the need for all Contracting States to the ECHR to respond to it in a consistent manner, is central to the Court’s conclusion on extraterritorial jurisdiction. In the section of the decision in Duarte addressing this issue, the Court noted that “the problem of climate change is of a truly existential nature for humankind” (§194). This reality is equally emphasised in KlimaSeniorinnen (§421), where the Court further highlighted the risks associated with global warming exceeding what it refers to as “the currently required 1.5°C limit” (§§432, 436, 558).
Both rulings further refer to the “concurrent responsibility” of States in relation to climate change (KlimaSeniorinnen §443; Duarte §202), with “each State [having] its own responsibilities within its own territorial jurisdiction” (KlimaSeniorinnen §443). That responsibility is “to put in place the necessary regulations and measures aimed at preventing an increase in GHG concentrations in the Earth’s atmosphere and a rise in global average temperature beyond levels capable of producing serious and irreversible adverse effects on human rights” (KlimaSeniorinnen §546). And on the basis that “each State can be held accountable for its share of the responsibility for [any] breach [of this obligation]”, the Court held that “[t]here is therefore no risk of a vacuum in the protection of the Convention rights, nor can there be any impunity by any of the respondent States in this context” (Duarte §202).
The approach of the Court is therefore to eliminate any vacuum of protection by establishing a uniform obligation to mitigate climate change, grounded in the 1.5°C temperature limit, across the “legal space” of the Convention. While it involves a narrower position than the German FCC on the existence of an extraterritorial obligation per se, it is an approach which, compared with that of Germany’s FCC, has the effect of ensuring a significantly higher level of protection for a person living in one State from the emissions of another State. It is also consistent with the first of the aims outlined above, provided that associations or individuals who meet the criteria for victim status laid down in KlimaSeniorinnen will pursue cases against their respective governments for inadequate climate action (and it is expected that this ruling will generate a new wave of domestic climate litigation throughout Europe).
Two qualifications are important to note. First, as cogently argued in a Third Party Intervention submitted in both KlimaSeniorinnen and Duarte, there is nothing safe about 1.5°C. This, however, is a point distinct from the question of any protection gap that may result from States having purely territorial obligations to mitigate climate change. Second, while the approach of the Court may be satisfactory from the perspective of effective protection against future harm, this is clearly not true for claims made by individuals from outside a State to a remedy for loss and damage partially attributable to its emissions. Insofar as the Court’s decision in Duarte may therefore be exploited by States contending, before other international courts and bodies, that any obligations to provide remedies for loss and damage ought to be territorially confined, it will hopefully be of relevance to the latter that the claim of the Applicants in Duarte, which was focused primarily on the future harm they face, did not concern this type of obligation (nor did they seek any monetary compensation as just satisfaction).
The decision on exhaustion of domestic remedies
Central to the Applicants’ claim as to why they were not obliged to exhaust domestic remedies – and of relevance to both of the aims noted above – was their argument that even the remedies granted by domestic courts in the successful climate cases in Europe were ineffective. They emphasised, in particular, the decision of the Dutch courts in Urgenda v The Netherlands, the first case in which a court held that a government was legally obliged to do more to reduce its emissions. In that case, the Dutch Supreme Court held that, owing to separation of powers considerations, its role was confined to defining what it termed the “absolute minimum” emissions reductions that the Netherlands was required to achieve (§7.5.1). In quantitative terms, this meant a figure reflecting the minimum of the Netherlands’ “fair share” of the global emissions reductions considered necessary in that case.
This is perhaps an understandable position for the first court confronted with this question to have taken. However, its difficulty from an effectiveness perspective is that, as has been pointed out in scientific literature on the decision which the Applicants in Duarte referred to, if all States pursue emissions reductions reflecting less-stringent interpretations of their fair share of the global reductions needed to hold global warming to a particular temperature limit, warming will significantly overshoot that limit. Furthermore, since Urgenda, both the German FCC (§§219, 230) and, more recently, the Brussels Court of Appeal (§201) have taken similarly deferential and minimalistic approaches to the question of how Germany’s and Belgium’s respective contributions to the necessary global emissions reductions ought to be determined.
The approach taken by domestic courts mirrors the fundamental problem with the Paris Agreement, which has so far rendered it incapable of ensuring that its principal goal of holding global warming to 1.5°C is achieved. The problem, in essence, is that its “bottom up” approach affords States significant latitude as to how they define their “Nationally Determined Contributions” (NDCs) towards this goal. And as was predicted, States have exploited this latitude by basing their NDCs on highly self-serving interpretations of what their respective contributions ought to be. The result is that we are now on course for a catastrophic over 3°C of warming by 2100.
The decision in Duarte notes the Applicants’ claim that the remedies granted in formally successful climate cases “were a prescription for warming catastrophically above 1.5°C” (§130). However, in its assessment of why the Applicants ought to have first brought their case before Portugal’s domestic courts (§§216-228), the Court did not engage with this point. Nor did it address the Applicants’ related claim that there was no realistic prospect of domestic courts developing effective remedies in sufficient time, having regard to the vanishing window within which to hold warming to 1.5°C.
Notably, the Court could have noted the Applicants’ position on the remedies granted in cases such as Urgenda – which was not contested by any of the Respondents – and still held that the Applicants ought to have sought a more stringent remedy from the Portuguese courts than those awarded by other domestic courts. Its decision instead to avoid engagement with the issue reflects the approach of the Committee on the Rights of the Child in the Sacchi climate case against five States, which was also found inadmissible for non-exhaustion of domestic remedies. The Committee’s decision in respect of Germany, for example, notes the Authors’ criticisms of the FCC decision in Neubauer (§7.3), which included those outlined above. However, it did not engage with these criticisms and rather inaccurately simply referred to an “absence of reasoning” on the part of the Authors as to why remedies in Germany are not effective (§9.17).
The second aim outlined above is therefore not reflected in the Court’s approach to exhaustion of domestic remedies. Of course, the approach it took in KlimaSeniorinnen to defining the positive obligation to mitigate climate change is equally relevant to this second aim and therefore a brief analysis of this approach is provided below.
The positive obligation to mitigate climate change in KlimaSeniorinnen
A number of features of the positive obligation to mitigate climate change set out in KlimaSeniorinnen are of particular note:
The first point to note in relation to these features is that there is an ostensible contradiction between the references (implicit and explicit) to equity and the Court’s indication that all Contracting States must achieve net zero CO2 emissions by mid-century, as envisaged by global 1.5°C emissions pathways. To say that all individual States must achieve net-zero at the same time that global emissions must reach net-zero is to adopt an approach to global burden-sharing known as “grandfathering”. As noted in the relevant literature, this approach is inconsistent with equity and therefore highly favourable to wealthier countries with greater historical responsibility. Within the Council of Europe, it would entail a vastly more onerous obligation, in equity terms, for, say, Albania, than it would for, say, Switzerland – assuming Albania were required to reach net zero by mid-century without an entitlement to climate finance from wealthier European States. And globally, it would mean that, for warming to be held to 1.5°C, other States would have to achieve emissions reductions which significantly exceed any reasonable measure of their fair share. The same, albeit to a lesser extent, is true for an “equal per capita”-based approach to burden-sharing, as it is also very favourable for wealthy/high responsibility States.
While it is not the function of the Strasbourg Court to make a philosophical judgement-call on the contested equity question, it is, as it held explicitly, concerned with the effective protection of rights against the impacts of climate change. And the latter requires consideration of the likelihood of other States achieving the emissions reductions they would need to achieve if European States were to pursue different approaches to burden-sharing. According to current practice, there is no possibility that some non-European States would achieve the level of reductions required of them, if most European States pursue emissions reductions which reflect relatively less stringent measures of their “fair share”. Furthermore, as an expert report relied on by the Applicants in Duarte emphasises, if States’ reductions follow such less stringent measures this decade, net zero CO2 by mid-century will be insufficient to limit warming to 1.5°C, and indeed limiting warming to this temperature will become impossible.
It is therefore submitted that an interpretation of the obligation outlined in KlimaSeniorinnen which is faithful to its emphasis on the effectiveness principle is one which focuses on the aspects of the Court’s ruling that emphasise the need for immediate, science-based emissions reductions reflecting due diligence. Science cannot tell us what is equitable. But it can tell us where, on the range of possible measures of States’ fair share of the necessary global reductions, they must aim for if warming is to be limited to 1.5°C. For “developed” States, this means doing everything within their power – i.e. acting with due diligence – to reduce their domestic emissions. It is, however, no longer possible for such States to achieve a 1.5°C-compatible approach to fair share through domestic emissions reductions alone. Therefore, limiting warming to 1.5°C will also require them to substantially increase their climate finance contributions to “developing” States, in line with Article 9 of the Paris Agreement, so as to enable the latter to reach net zero in time.
With time rapidly running out, it is hoped that this is how domestic courts interpret the obligation outlined in KlimaSeniorinnen.
In light of these aims, this post addresses certain aspects of the decision of the Grand Chamber in Duarte – which dismissed the Applicants’ claim as inadmissible both because they are not within the extraterritorial jurisdiction of the Respondent States other than Portugal (the Applicants’ home State) and on the basis that they ought to have exhausted domestic remedies in Portugal – and provides a brief comment on the judgment in the related KlimaSeniorinnen climate case. Both rulings have already been discussed extensively (including here, here, here, here, here and here).
The Court’s approach to extraterritorial jurisdiction
Of particular relevance to the first aim mentioned above are the arguments advanced by the Applicants as to why, in the absence of recognition of an extraterritorial obligation, they would find themselves within a “vacuum of protection”, and the response of the Court to that argument. As noted in the Court’s decision (§125), the Applicants contended that the effective protection of their rights required recognition that they fell within the extraterritorial jurisdiction of the Respondent States other than Portugal, for the purpose of their obligation to mitigate climate change. The basis for this claim was that across Europe there is a variation in vulnerability to climate impacts and in the adaptive capacity of countries. As the IPCC has pointed out, “
To demonstrate how this variation in vulnerability and adaptive capacity could leave them within a vacuum of protection, the Applicants highlighted the decision of Germany’s Federal Constitutional Court (“FCC”) in the Neubauer et al. climate case. The complainants in that case contended that Germany’s 2030 emissions target was inadequate because it was not aligned with the 1.5°C temperature limit. However, in upholding the constitutionality of the 2030 target, which the FCC found to be “possibly still oriented towards a target of 2°C”, it held that “t is not evident that the health consequences arising from 2°C global warming and from the associated climate change in Germany could not be alleviated by supplementary adaptation measures in a manner that would be sufficient under constitutional law” (§167, emphasis added).
Among the complainants in Neubauer et al. were a group of individuals from Bangladesh and Nepal. The position taken by the FCC in relation to Germany’s extraterritorial obligations towards these complainants, which is quoted in the decision in Duarte (§65), can be summarised as follows:
- While the constitutional duty of protection from climate impacts may in principle extend to people living outside Germany, it cannot have the same content as the duty owed to people in Germany (§§175-176);
- This is because the duty is fulfilled through a combination of emissions reductions and adaptation measures which are “inextricably linked” and the balance between them is to be determined politically (§§177, 181);
- Further, “it is practically impossible for the German state to afford protection to people living abroad by implementing adaptation measures there […]. Rather, it is the task of the states concerned to select and implement the necessary measures” (§178);
- “This does not exclude Germany from assuming responsibility, either politically or under international law, for ensuring that positive steps are taken to protect people in poorer and harder-hit countries”, including by providing climate finance in accordance with Article 9 of the Paris Agreement (§179);
- There was no violation of any obligation to the complainants from Bangladesh and Nepal because “it cannot be claimed that the legislator has taken no measures whatsoever to limit climate change or has only adopted provisions and taken measures that would be manifestly unsuitable or completely inadequate for achieving the required protection goal”, with the FCC noting that Germany has ratified the Paris Agreement and based its climate change legislation on the obligation to observe it (§180).
The thrust of the FCC’s decision is therefore that Germany can align its emissions targets with 2°C, instead of 1.5°C, because Germany has the capacity (according to the FCC) to adapt to impacts at that level of warming, while it is “the task of the states concerned” – Bangladesh and Nepal – to adopt measures to adapt to the consequences of this choice. It is hardly surprising that this position has been the subject of criticism. Glaringly absent from the FCC’s analysis was any consideration of whether the adoption by Bangladesh and Nepal of adaptation measures would even be capable of protecting their populations from the kinds of impacts they would be exposed to at 2°C. The scenes of devastation from the unprecedented flooding events that have hit South Asia in recent years, at just 1.2°C of global warming, are perhaps sufficient to answer this question.
The Applicants referred to the FCC’s decision as demonstrating how they, being residents in a particularly vulnerable European country with relatively limited adaptive capacity, could end up caught in a vacuum of protection if States’ obligations to mitigate climate change were territorially confined. However, the force of this argument diminishes when the broader existential threat of the climate crisis is kept in view. After all, if we cross the various catastrophic tipping points in the climate system (five of which we are already on the brink of), the differences between the adaptive capacities of different countries lose their relevance: by definition, no adaptation measures will protect against a scenario in which the planet ceases to be capable of sustaining human life.
It is clear from the decision in Duarte, read alongside the judgment in KlimaSeniorinnen, that the possibility of such a scenario, and the need for all Contracting States to the ECHR to respond to it in a consistent manner, is central to the Court’s conclusion on extraterritorial jurisdiction. In the section of the decision in Duarte addressing this issue, the Court noted that “the problem of climate change is of a truly existential nature for humankind” (§194). This reality is equally emphasised in KlimaSeniorinnen (§421), where the Court further highlighted the risks associated with global warming exceeding what it refers to as “the currently required 1.5°C limit” (§§432, 436, 558).
Both rulings further refer to the “concurrent responsibility” of States in relation to climate change (KlimaSeniorinnen §443; Duarte §202), with “each State [having] its own responsibilities within its own territorial jurisdiction” (KlimaSeniorinnen §443). That responsibility is “to put in place the necessary regulations and measures aimed at preventing an increase in GHG concentrations in the Earth’s atmosphere and a rise in global average temperature beyond levels capable of producing serious and irreversible adverse effects on human rights” (KlimaSeniorinnen §546). And on the basis that “each State can be held accountable for its share of the responsibility for [any] breach [of this obligation]”, the Court held that “[t]here is therefore no risk of a vacuum in the protection of the Convention rights, nor can there be any impunity by any of the respondent States in this context” (Duarte §202).
The approach of the Court is therefore to eliminate any vacuum of protection by establishing a uniform obligation to mitigate climate change, grounded in the 1.5°C temperature limit, across the “legal space” of the Convention. While it involves a narrower position than the German FCC on the existence of an extraterritorial obligation per se, it is an approach which, compared with that of Germany’s FCC, has the effect of ensuring a significantly higher level of protection for a person living in one State from the emissions of another State. It is also consistent with the first of the aims outlined above, provided that associations or individuals who meet the criteria for victim status laid down in KlimaSeniorinnen will pursue cases against their respective governments for inadequate climate action (and it is expected that this ruling will generate a new wave of domestic climate litigation throughout Europe).
Two qualifications are important to note. First, as cogently argued in a Third Party Intervention submitted in both KlimaSeniorinnen and Duarte, there is nothing safe about 1.5°C. This, however, is a point distinct from the question of any protection gap that may result from States having purely territorial obligations to mitigate climate change. Second, while the approach of the Court may be satisfactory from the perspective of effective protection against future harm, this is clearly not true for claims made by individuals from outside a State to a remedy for loss and damage partially attributable to its emissions. Insofar as the Court’s decision in Duarte may therefore be exploited by States contending, before other international courts and bodies, that any obligations to provide remedies for loss and damage ought to be territorially confined, it will hopefully be of relevance to the latter that the claim of the Applicants in Duarte, which was focused primarily on the future harm they face, did not concern this type of obligation (nor did they seek any monetary compensation as just satisfaction).
The decision on exhaustion of domestic remedies
Central to the Applicants’ claim as to why they were not obliged to exhaust domestic remedies – and of relevance to both of the aims noted above – was their argument that even the remedies granted by domestic courts in the successful climate cases in Europe were ineffective. They emphasised, in particular, the decision of the Dutch courts in Urgenda v The Netherlands, the first case in which a court held that a government was legally obliged to do more to reduce its emissions. In that case, the Dutch Supreme Court held that, owing to separation of powers considerations, its role was confined to defining what it termed the “absolute minimum” emissions reductions that the Netherlands was required to achieve (§7.5.1). In quantitative terms, this meant a figure reflecting the minimum of the Netherlands’ “fair share” of the global emissions reductions considered necessary in that case.
This is perhaps an understandable position for the first court confronted with this question to have taken. However, its difficulty from an effectiveness perspective is that, as has been pointed out in scientific literature on the decision which the Applicants in Duarte referred to, if all States pursue emissions reductions reflecting less-stringent interpretations of their fair share of the global reductions needed to hold global warming to a particular temperature limit, warming will significantly overshoot that limit. Furthermore, since Urgenda, both the German FCC (§§219, 230) and, more recently, the Brussels Court of Appeal (§201) have taken similarly deferential and minimalistic approaches to the question of how Germany’s and Belgium’s respective contributions to the necessary global emissions reductions ought to be determined.
The approach taken by domestic courts mirrors the fundamental problem with the Paris Agreement, which has so far rendered it incapable of ensuring that its principal goal of holding global warming to 1.5°C is achieved. The problem, in essence, is that its “bottom up” approach affords States significant latitude as to how they define their “Nationally Determined Contributions” (NDCs) towards this goal. And as was predicted, States have exploited this latitude by basing their NDCs on highly self-serving interpretations of what their respective contributions ought to be. The result is that we are now on course for a catastrophic over 3°C of warming by 2100.
The decision in Duarte notes the Applicants’ claim that the remedies granted in formally successful climate cases “were a prescription for warming catastrophically above 1.5°C” (§130). However, in its assessment of why the Applicants ought to have first brought their case before Portugal’s domestic courts (§§216-228), the Court did not engage with this point. Nor did it address the Applicants’ related claim that there was no realistic prospect of domestic courts developing effective remedies in sufficient time, having regard to the vanishing window within which to hold warming to 1.5°C.
Notably, the Court could have noted the Applicants’ position on the remedies granted in cases such as Urgenda – which was not contested by any of the Respondents – and still held that the Applicants ought to have sought a more stringent remedy from the Portuguese courts than those awarded by other domestic courts. Its decision instead to avoid engagement with the issue reflects the approach of the Committee on the Rights of the Child in the Sacchi climate case against five States, which was also found inadmissible for non-exhaustion of domestic remedies. The Committee’s decision in respect of Germany, for example, notes the Authors’ criticisms of the FCC decision in Neubauer (§7.3), which included those outlined above. However, it did not engage with these criticisms and rather inaccurately simply referred to an “absence of reasoning” on the part of the Authors as to why remedies in Germany are not effective (§9.17).
The second aim outlined above is therefore not reflected in the Court’s approach to exhaustion of domestic remedies. Of course, the approach it took in KlimaSeniorinnen to defining the positive obligation to mitigate climate change is equally relevant to this second aim and therefore a brief analysis of this approach is provided below.
The positive obligation to mitigate climate change in KlimaSeniorinnen
A number of features of the positive obligation to mitigate climate change set out in KlimaSeniorinnen are of particular note:
- it is said to stem from the principle that ECHR obligations must be interpreted so as to “guarantee rights that are practical and effective, not theoretical and illusory” (545);
- it is described as being “in line with” the obligations under the UNFCCC and the Paris Agreement (546), both of which are founded on the principle of equity, to which the Court refers in its application of the obligation to Switzerland’s policies (§571);
- the obligation, as generally defined as applying to all Contracting States, is anchored in the need to achieve carbon neutrality within three decades (§547, 548, 550(a)), a requirement which is derived from the global emissions pathways outlined in the IPCC’s Special Report on 1.5°C (§109);
- the Court emphasises the need for immediate action and binding intermediate reduction goals to ensure that achievement of carbon neutrality remains feasible and to avoid imposing a disproportionate burden on future generations (§549, 550(b));
- it requires emissions targets to be updated with due diligence and based on best available science (§546, 550(d));
- in finding Switzerland in breach of this obligation, the Court noted that “under its current climate strategy, Switzerland allowed for more GHG emissions than even an ‘equal per capita emissions’ quantification approach would entitle it to use” (569).
The first point to note in relation to these features is that there is an ostensible contradiction between the references (implicit and explicit) to equity and the Court’s indication that all Contracting States must achieve net zero CO2 emissions by mid-century, as envisaged by global 1.5°C emissions pathways. To say that all individual States must achieve net-zero at the same time that global emissions must reach net-zero is to adopt an approach to global burden-sharing known as “grandfathering”. As noted in the relevant literature, this approach is inconsistent with equity and therefore highly favourable to wealthier countries with greater historical responsibility. Within the Council of Europe, it would entail a vastly more onerous obligation, in equity terms, for, say, Albania, than it would for, say, Switzerland – assuming Albania were required to reach net zero by mid-century without an entitlement to climate finance from wealthier European States. And globally, it would mean that, for warming to be held to 1.5°C, other States would have to achieve emissions reductions which significantly exceed any reasonable measure of their fair share. The same, albeit to a lesser extent, is true for an “equal per capita”-based approach to burden-sharing, as it is also very favourable for wealthy/high responsibility States.
While it is not the function of the Strasbourg Court to make a philosophical judgement-call on the contested equity question, it is, as it held explicitly, concerned with the effective protection of rights against the impacts of climate change. And the latter requires consideration of the likelihood of other States achieving the emissions reductions they would need to achieve if European States were to pursue different approaches to burden-sharing. According to current practice, there is no possibility that some non-European States would achieve the level of reductions required of them, if most European States pursue emissions reductions which reflect relatively less stringent measures of their “fair share”. Furthermore, as an expert report relied on by the Applicants in Duarte emphasises, if States’ reductions follow such less stringent measures this decade, net zero CO2 by mid-century will be insufficient to limit warming to 1.5°C, and indeed limiting warming to this temperature will become impossible.
It is therefore submitted that an interpretation of the obligation outlined in KlimaSeniorinnen which is faithful to its emphasis on the effectiveness principle is one which focuses on the aspects of the Court’s ruling that emphasise the need for immediate, science-based emissions reductions reflecting due diligence. Science cannot tell us what is equitable. But it can tell us where, on the range of possible measures of States’ fair share of the necessary global reductions, they must aim for if warming is to be limited to 1.5°C. For “developed” States, this means doing everything within their power – i.e. acting with due diligence – to reduce their domestic emissions. It is, however, no longer possible for such States to achieve a 1.5°C-compatible approach to fair share through domestic emissions reductions alone. Therefore, limiting warming to 1.5°C will also require them to substantially increase their climate finance contributions to “developing” States, in line with Article 9 of the Paris Agreement, so as to enable the latter to reach net zero in time.
With time rapidly running out, it is hoped that this is how domestic courts interpret the obligation outlined in KlimaSeniorinnen.