Dr Sava Jankovic, Director for Research and Development at the Institute of Science and Culture in Oslo, Researcher at the Institute of Legal Studies of the Polish Academy of Sciences.


The Federal Constitutional Court, in its recent Order 1 BvR 2656/18 on climate protection urged the German government to make immediate efforts to meet long-term greenhouse gas reduction goals contained in the 2019 Climate Change Act (KSG) and the Climate Action Plan 2050 to give meaningful effect to the 2015 Paris Agreement. The Court criticised and ordered the amendment of the provisions of the 2019 Climate Change Act, which sets up an imprecise and inadequate strategy for reaching carbon neutrality in 2050. The Court stressed that such a faulty strategy is likely to violate ‘virtually any freedom’ of both present and future generations. Human rights, like the right to life, physical integrity and property might also be breached, if the State does not address the climate change correctly.

The ruling contains broad international law underpinnings, from international contractual commitments to human rights. Indeed, it could not be otherwise, as climate change is a global issue. As the Court itself noted,

‘’As a climate protection requirement, Article 20a GG (German Constitution) has an international dimension, which contains an obligation that inevitably goes beyond the national law available to the individual state alone and is to be understood as a reference also to the level of international action.’’ (para. 201)

The Court referred in 26 paragraphs to the Paris Agreement – the so far only universal treaty that regulates the climate change problem comprehensively – highlighting its most core aspects: a) Limiting the global temperature increase to values between 2 °C and 1.5 °C above pre-industrial levels, b) fostering international cooperation to this end, and c) preventing the negative impact of climate change on human rights and freedoms. The piece will now lay down these three aspects by providing direct references to key passuses from the Court’s ruling. Although the analysed aspects did not form the crux of the ruling, they underpinned the Court’s reasoning and provide a convenient benchmark for commentaries on the state of climate change law in national legal orders, which is a source of customary international law.

  1. Limiting the global temperature increase to values between 2 °C and 1.5 °C above pre-industrial levels

This is the paramount aim of the Paris Agreement, stipulated in Article 2(1)(a). The partially unconstitutional KSG is a form of the national implementation of the Paris Agreement’s aims and the Court reminded about this at the very beginning,

‘’According to § 1 sentence 3 KSG, the basis is […] the obligation under the Paris Agreement […], according to which the increase in global average temperature is to be limited to well below 2° C and, if possible, to 1.5 ° C compared to the pre-industrial level, in order to keep the effects of global climate change as low as possible […]’’ (para. 1)

The Court went further to assert that Article 20a of the GG on the protection of natural foundations of life and animals embraces the duty to protect from climate change in accordance with the Paris target, endowing thereby the limits with a constitutional rang.

‘’In exercising its concretization mandate and its concretization prerogative, the legislature has currently determined the climate protection goal of Art. 20a GG through § 1 sentence 3 KSG to the effect that the global average temperature should rise to well below 2 ° C and, if possible, to 1.5 ° C is to be limited compared to the pre-industrial level’’ (para. 208)

It is worth noting that the Court applied a very strict reading of the norms allowance. The Court based such an approach on the gloomy climate change outlook and the resulting necessity to reach the Paris Agreement’s goal as soon as possible. According to the Court, Germany should endeavour to substantially overcome the minimum obligation, preferably by reaching the 1.5° C threshold. As the Court observed,

‘’The Secretariat of the United Nations Framework Convention on Climate Change came to the conclusion that the greenhouse gas emissions to be expected worldwide by 2030 are incompatible with reduction paths that would limit global warming to 1.5 ° C or 2 ° C […] Rather, the emissions to be expected coincided with paths that indicated a temperature increase of 3 ° C by the year 2100’’ (para. 10)

’In fact, there are indications that, according to the reduction path regulated in the Climate Change Act until 2030, an overall reduction that could correspond to a German contribution to limiting global warming to 1.5 ° C would no longer be feasible. […] The compliance with the reduction contribution corresponding to a 2 ° C target would appear to be more possible. However, this was not sufficient for the Paris target of “well below 2 ° C” mentioned in § 1 sentence 3 KSG’’. (para. 166)

‘’In the meantime, the legislature has given up on its stated endeavours in specifying Article 20a of the Basic Law to limit the temperature rise to 1.5 ° C as far as possible (§ 1 sentence 3 KSG).’’ (para. 242)

It is thus conspicuous that the German Court gave weighty attention to the paramount goal of the Paris Agreement, first by declaring the thresholds a constitutional principle and second by urging Germany to try its utmost towards reaching the upper limit. It would not be a mistake to position the Court’s Order against its previous Order from 2004, which declared that the “central norms for the protection of the environment” are part of jus cogens, that is ones, which are given the highest priority and which should be protected by all means. This trend is visible in climate litigations around the world, where courts (the Supreme Court of the Netherlands’s ruling is a good recent example) heavily rely on the Paris Agreement’s goal and the effects of climate change on constitutionally protected values.

  • Fostering international cooperation to fulfil the Paris Agreement’s assumptions

The Paris Agreement abounds in cooperative (and sometimes obligatory) clauses. They are evident, inter alia, in Article 4(2) of the Agreement, which provides that all Parties should prepare, communicate and maintain successive their Nationally Determined Contributions (NDCs); Article 5(1), which provides that Parties should take action to conserve and enhance, as appropriate, sinks and reservoirs of greenhouse gases; Article 7(7) stipulating that Parties should strengthen their cooperation on enhancing action on adaptation; Article 9(1), which provides that developed country Parties shall provide financial resources to assist developing country Parties with respect to both mitigation and adaptation; or Article 10(1), which holds that Parties share a long-term vision on the importance of fully realizing technology development and transfer. The German Court referred to the obligation of international cooperation in various spheres. It underlined, for example, that Germany should provide financial assistance (as a positive measure to protect people) to poorer places in their efforts to adapt to climate change (para. 179) or may transfer extra-mandatory emission reduction benefits to other signatories to the Paris Agreement, once a reliable credit system emerges (para. 226). Yet, apart from referring to the cooperative framework established by the Paris Agreement, the Court seemed to interpret Article 20a GG in light of a thoroughgoing international cooperation obligation, with a strict goal-orientated stance on climate change. In particular, it demanded that Germany besides reaching an agreement should implement it and adhere to it; that Germany in joint climate action can neither set a low example for other States nor follow low standards of other States, if they exhibit such; finally, Germany is obliged to look for or create a more viable cooperation network, should Paris Agreements assumptions prove insufficient. As the Court remarked,

‘’The international dimension of Art. 20a GG as a climate protection requirement is not limited to the task of looking for a solution to the climate problem on an international level and, if possible, reaching an agreement for it. Rather, the constitutional climate protection requirement includes the implementation of agreed solutions’’. (para. 201)

‘’The state could not evade its responsibility by referring to greenhouse gas emissions in other states […] Conversely, the specific dependency on the international community of states implies the constitutional necessity to Actually taking internationally agreed climate protection measures as far as possible. Precisely because the state can only successfully implement the climate protection requirement imposed on it in Article 20a of the Basic Law in international cooperation, it must not set any incentives for other states to undermine this cooperation.’’ (para. 203).

‘’If the temperature target agreed in Article 2(1)(a) of the PA proves to be inadequate to achieve sufficient climate protection, the obligation under Article 20a of the Basic Law to seek a solution to the climate protection problem at the international level is also updated; In particular, efforts should be made to reach stricter agreements.’’ (para. 212)

It is evident from the text of the ruling that the Court opted for a profound international cooperation perspective, exceeding the Paris Agreement framework. The Paris Agreement undoubtedly constitutes a bedrock and remains in force for Germany, but other avenues should be explored too.

  • Efforts to prevent the negative impact of climate change on the rights and freedoms

The impact of climate change on the rights and freedoms is not expressis verbis articulated in the Paris Agreement’s text, but indeed lies at the crux of the Agreement and can unequivocally be deduced from several preambular phrases, like the ‘response to the urgent threat of climate change’, ‘particular vulnerabilities of food production systems to the adverse impacts of climate change’ or ‘acknowledging that climate change is a common concern of humankind’. The Paris Agreement in Article 8 likewise mentions ‘extreme weather events and slow onset events’ as consequences of global warming. The ruling of the Court devotes much space to the effects of climate change on the environment, alluding, inter alia, to extreme climate events like heatwaves, forest and land fires, cyclones, heavy rains, floods, avalanches or landslides. The Court directly mentions a potential violation of human rights committed by a State, which does not adequately address the issue of climate protection.

’’The complainants can partially assert that their fundamental right to life and physical integrity (Article 2, Paragraph 2, Clause 1 of the Basic Law) and some of them in their fundamental right to property (Article 14, Paragraph 1 of the Basic Law) have been violated (see below II 1, CI), because with the Climate Change Act the state may have taken insufficient measures to reduce greenhouse gas emissions and limit global warming.’’ (para. 90)

Given that the effects of climate change will be particularly experienced by future generations, the German Court opined in favour of the sustainable development and intergenerational equity dimension of climate change, which nowadays is a preferred viewpoint. In that, the Court acknowledged the preambular clause of the Paris Agreement that the ‘Parties should, when taking action to address climate change, respect, promote … the intergenerational equity’.

‘’Art. 20a GG sets limits to the legislature’s decisions – especially those with irreversible consequences for the environment – and imposes a special duty of care on them, also with responsibility for future generations’’ (para. 229)

This creates a presumption of the possible precedence of environmental law norms over others, which the Court, in fact, corroborated in the ruling (para. 198). In addition, the Court concluded that virtually any freedom of the future generations will be at stake if Germany does not create a viable agenda for timely emissions reduction. This stands in conformity with the Paris Agreement’s preambular clause that States while taking actions on climate change should ‘respect, promote and consider their respective obligations on human rights’. As the Court observed,

‘’Virtually any freedom is potentially affected, because today almost all areas of human life are associated with the emission of greenhouse gases (above marginal no. 37) and can thus be threatened by drastic restrictions after 2030.’’ (para. 117)

’’It follows from the principle of proportionality that one generation must not be allowed to consume large parts of the CO2 budget with a comparatively mild reduction burden if, at the same time, this leaves the following generations with a radical reduction burden – described by the complainants as an “emergency stop” – and their Life would be subjected to a serious loss of freedom.’’ (para. 192)

Apart from taking a right-based stance, the Court can be criticized for doing it in a depleted manner. It is, for instance, regrettable that the Court rejected the claimants’ assumption to the right to a healthy environment and did not use the chance to elaborate on the individual exitance of such a right in international law, despite labelling section B.II.5 of its ruling as ‘Basic right to a climate and environmentally friendly way of life’. The phrase indeed suggests the existence of such a right (be it in the German legal order or internationally), but the unwillingness of the Court to dwell upon this issue more, leaves scholars again in limbo, between two opposing epistemological camps. It could also be lamented that the Court did not decide to extend the applicability of international responsibility for human rights violations in climate change matters outside the German borders, by simply blaming its inability to manage adaptation and mitigation measures in particular countries, viz. Nepal and Bangladesh (para. 178). Furthermore, the Court could have made more efforts to elucidate particular human rights endangered by adverse effects of climate change, such as the right to health, life, food, water and sanitation, rights of the child – following the practice of the UN Special Rapporteur -, which would add more persuasiveness and clarity to certain parts of the Order. Instead, the Court only peripherally mentioned possible affected human rights (para. 90), concentrating predominantly on the restriction of freedoms, which will result not from the climate change per se, but from an accelerated consumption of the CO2 budget until 2030 (para. 186) and a need for faster emission reduction after the year 2030 (para. 142). The two categories of endangered freedoms and rights are incomparable in weight.


The ruling despite being issued by a national body and criticized on account of its shortcomings has been received with great acclaim by international law scholars. It should be borne in mind that courts also operate within certain legal avenues and that every judgement that adds up to a good global cause, such as global warming, is praiseworthy (see similar verdicts in France, Ireland and Canada). All in all, although the ruling 1 BvR 2656/18 pertains to the constitutionality of the 2019 Climate Change Act in the first place, it constitutes a timely and necessary reminder for the German government of its obligations under the Paris Agreement. The Court analysed a purely global issue and explicitly urged Germany to fulfil its international commitments on climate change, many of each enshrined in the Paris Agreement. From the ruling, it is evident that the Paris Agreement is not only the basis for the questioned Climate Change Act and other Germany’s climate plans and agendas but also that its main provisions are soon to be endowed with a binding constitutional character. It also flows from the ruling that States have to cooperate on the climate change problem, doing their best and are not allowed to impede that process through national acts, negligence or drawing substandard examples from other States. What is more, Germany, as a wealthy and developed State, has an additional motivation and obligation to propel the climate offensive, which others should follow. Lastly, the Court acknowledged that fundamental rights and freedoms are at very stake in the looming climate change crisis and that inappropriate national climate change strategies can violate rights and freedoms in like manner. The Court underscored the universal dimension of climate change effects and adaptation strategies, meaning that human rights will be endangered in every place around the globe if a joint emission reduction action fails or if the countries choose inadequate adaptation and mitigation techniques.