Verein KlimaSeniorinnen and Others v Switzerland (Application no. 53600/20)
Response to the Respondent’s written answers to the questions communicated by
the Court to the parties on 16 March 2023 to be addressed in their oral submission
at the hearing before the Grand Chamber

Table of contents
1. Introduction ........................................................................................ 3
2. Summary of the written answers of the Respondent to the Court’s questions ... 3
3. Resolving fundamental misconceptions underlying the written answers of the
Respondent.......................................................................................... 4
3.1. A quantitative assessment of Switzerland’s “fair share” is indispensable todetermine the scope of the Respondent’s obligation to protect ................ 4
3.2. The “fair share” contribution requested by the Applicants does not put an
inequitable burden on the Respondent .................................................. 8
3.3. The IPCC’s global emission reduction pathways are not “fair share”
pathways ........................................................................................... 9
4. Detailed reply to the Respondent’s written answers to the questions posed by
the Court .......................................................................................... 11
4.1. The Respondent did not approach the question of what level of climate
protection must be ensured to be in line with the 1.5°C limit with due
diligence .......................................................................................... 11
4.2. The decision-making process prior to establishing a legislative andadministrative framework did not involve the carrying out of“appropriate” investigations and studies and consequently did not result ina “fair share” contribution by Switzerland ........................................... 15
4.3. Indicators of fairness put forward by the Respondent are not in line with
relevant principles, including those set out by the Respondent in its
internal working document ............................................................... 16
4.4. The Respondent did not determine any national carbon budget as a “fairshare” of the remaining global budget ................................................. 19
4.4.1. No overall national budget has been adopted in relation to theglobal emissions budget ........................................................ 19
4.4.2. The Respondent’s “budgetary approach” leads to a completely
inadequate “national budget” ............................................... 201

4.4.3.

What if the Respondent adopted a national budget based on the
Policy Brief? ........................................................................ 20
4.5. The alleged alignment of the Respondent with the IPCC global emission
trajectories did and will not result in a “fair share” contribution by
Switzerland ...................................................................................... 21
4.5.1. The development of NDC in 2015 based on global (and thus not“fair”) pathways and with a view to the now outdated 2°Climit…….... ........................................................................ 21
4.5.2. The alleged reassessment of NDC in 2020 was merely a formal
update and did not make it “fair” .......................................... 23
4.5.3. The alleged planned reassessment of NDC in 2025 is unlikely totake place and to make it “fair” ............................................. 23
4.6. The Respondent’s critique of expert studies is superficial and unfounded25
4.6.1. No agreed methodology for calculating “fair shares” ............... 25
4.6.2. Critique of the CAT and Climate Analytics Studies ................. 26
4.6.3. Critique of the Rajamani et al. study ...................................... 29
4.6.4. The costs of reducing emissions within a few years would be very
high…………… ................................................................. 30
4.6.5. “Not all” qualitative assessments of equity can be translated intoquantitative results .............................................................. 31
4.6.6. The studies put forward by the Applicants provide the best
available science to inform the scope of the Respondent’s
obligation to protect ............................................................. 31
4.7. The requested emission reductions can be achieved by the Respondent . 31
4.7.1. The Respondent fails to meet its own (inadequate) climate targets
and emissions are going up ................................................... 31
4.7.2. The Respondent’s ability to meet its NDC and its commitments
under the Paris Agreement pursuant to the available and planned
climate mitigation measures ................................................. 32
5. Request for expert hearing .................................................................... 33

2

1.

Introduction

1

By letter of 16 March 2023, the Court invited the parties to address specificquestions in their oral submissions at the hearing on 29 March 2023. Instead,the Respondent submitted written answers (“written answers”) and material in
support, including a Policy Brief by Prof. Dr. Lucas Bretscher from 20121(“Policy Brief”) at Annex 1 and an internal working document commissionedby the Federal Office for the Environment (“FOEN”) titled “Klimawandel unddas Paris Abkommen: Welcher NDC der Schweiz ist ‘fair und ambitiös’?” from2020 (“internal working document”) at Annex 2. This was only provided to
the Applicants immediately before the hearing on 29 March 2023.

2

In order to reply to the Respondent’s written answers, the Applicants havenumbered the Respondent’s written answers (see accompanying Annex
document “doc.” 1, referred to as “Respondent, para.”).

3This submission is limited to responding to the Government’s written answers
and, in so far as relevant, to the additional material filed.

2.

Summary of the written answers of the Respondent to the Court’s questions

4

The Respondent contends that Switzerland's emission targets constitute a faircontribution toward holding the global temperature below 1.5°C. It claims that
its Nationally Determined Contribution (“NDC”) has been determined byreference to principles and indicators such as responsibility, capacity,
Switzerland’s small share of global emissions and the fact that its mitigation
costs are high. This part of the Respondent’s written answers can becharacterised as the “qualitative assessment” of its “fair share.” To substantiate
its qualitative assessment, the Respondent submitted an internal working
document which allegedly formed a basis of the NDC and which further setsout relevant principles and indicators for fairness.

5

The second part of the Respondent’s written answers relates to what can becharacterised as the “quantitative assessment” of its “fair share.” This partaddresses the question of whether it is possible to operationalise the principles
and indicators of the qualitative assessment into concrete national carbon

BRETSCHGER, Climate Policy and Equity Principles: Fair Burden Sharing in a Dynamic World, Centerof Economic Research at ETH Zurich, Policy Brief 12/16, March 2012 (Respondent, Annex 1). It
should be noted that this Policy Brief has been published in an updated version on the website of ETH
Zurich in June 2012 (link) and in October 2013 after undertaking a peer review process in a further
updated version in the journal Environment and Development Economics Vol. 18, No. 5, pp. 517–
536 (link).
1

3

budgets and related emission targets. The Respondent alleges that because
there is not one “agreed methodology,”, all attempts at quantifying a “fairshare” are inherently subjective, including the studies put forward by the
Applicants. This is also why, according to the Respondent, theIntergovernmental Panel on Climate Change (“IPCC”) has refrained fromproposing national budgets. The Respondent asserts that due to the lack of anagreed methodology, it cannot be required to provide a quantitative
substantiation of the fairness of its emission reduction targets.
6

Despite challenging the concept of quantification of emission reduction targets,
the Respondent put forward two bases on which it claims to have determined
its emission reduction targets. The first is the Policy Brief from 2012, which
purports to quantify national emission budgets for holding the global averagetemperature increase to below 2°C based on fairness principles. The second is
the IPCC’s global emission reduction pathways. The Respondent alleges that its
emission targets are in line with these global emission reduction pathways,
which would suffice to meet a “fair share” contribution towards the global
mitigation limit of 1.5°C.

7

The Respondent then goes on to allege that the “fair share” contribution
requested by the Applicants based on several studies is far too costly and thus
is an inequitable burden for Switzerland.

3.

Resolving fundamental misconceptions underlying the written answers of the
Respondent

8

Three fundamental misconceptions underlie the Respondent’s approach. First,
that quantifications of “fair share” are inherently subjective. Secondly, that the
Respondent cannot achieve the reduction requirements that derive from effort
sharing studies, Thirdly, that average global emission reduction trajectories
provide appropriate benchmarks for a country's emission reduction efforts.

3.1. A quantitative assessment of Switzerland’s “fair share” is indispensable todetermine the scope of the Respondent’s obligation to protect
9

The importance of conducting a quantitative assessment of a country's “fairshare” and indeed the feasibility of such a calculation can best be illustrated byreference to the Policy Brief, upon which Switzerland allegedly based its
emissions targets. The Policy Brief defines emission budgets for selected
countries, but not for Switzerland. To assess whether the methodology put
4forward in the Policy Brief can indeed result in a national emission budget thatwould validate Switzerland's current and planned emission reduction targets,
the Applicants commissioned an independent scientific report by two scientists
with extensive experience in effort-sharing modelling (Dr. Yann Robiou du Pont
and Dr. Zebedee Nicholls, “Calculation of an emissions budget for Switzerland
based on Bretschger’s (2012) methodology”, 26 April 2023, “Expert Report”,
doc. 2). The Expert Report applied the methodology of the Policy Brief to theremaining global 1.5°C budget from the IPCC’s Sixth Assessment Report(“AR6”) and determined a remaining budget for Switzerland of 381 MtCO2eq
from 1st Jan 2022 onwards. Notably, the Expert Report calculated that, basedon Switzerland's current and planned emission reduction targets, this budget
would be depleted by 2030/2033 (Expert Report, Figures B and C). On thebasis of its current and planned targets, Switzerland would apportion itself
0.2073% of the remaining global CO2 budget as of 2022, compared to a
population share of 0.1099% (Expert Report, p. 9). For Switzerland to staywithin the budget as defined by the methodology of its “own” Policy Brief, itwould need to achieve net-zero emissions by 2040 (Expert Report, Figure A),
and thus well before its current target of net-zero by 2050.
10Furthermore, the Expert Report notes several shortcomings of the methodology
in the Policy Brief which make it unsuitable to inform “fair share” targets forcountries (below §51). The Applicants, on the other hand, have alreadysubmitted studies that base their results on a broad assessment of the existing
literature and are for this reason a better basis to assess the fairness of
Switzerland's targets (Observations of 2 December 2022 “Obs.”, §§ 41-43).
Despite these shortcomings in the Policy Brief, the Expert Report clearly showsthat even when assessed against this methodology, the Respondent’s climate
strategy falls far short. Any quantitative assessment necessitates the conclusionthat the remaining budget that Switzerland has apportioned to itself is too large
for it to remain below the 1.5°C temperature limit.

11

Furthermore, contrary to what the Respondent alleges, the IPCC has engaged
with assessments of effort-sharing methodologies, particularly in its Fourth and
Fifth Assessment Reports (“AR4” and “AR5”; cf. Obs., §40). In its most recent
AR6, the IPCC explicitly recognises the importance for countries to explain
how fairness principles are “operationalised” and to express their targets in5

terms of the portion of the remaining global budget, 2 which the Respondent
has failed to do. The IPCC recognises that since the feasibility of agreeing on
one methodology to divide the remaining carbon budget “within the climatechange regime is low,” the onus is on actors outside the regime to developthese, giving special attention to the role of Courts.3 This is because as the IPCC
set out: “it is only in relation to such a ‘fair share’ that the adequacy of a state’scontribution can be assessed in the context of a global collective action
problem.”4
12

Clearly, and all the more so in the absence of any quantitative assessment, thedetermination of Switzerland's “fair share” of the remaining global emission
budget is an appropriate way for Courts to determine the scope of the
Respondent’s duty to protect. The Respondent rightly does not claim otherwise
in its written answers. Notably, the Dutch Courts for instance based theirrespective judgements in Urgenda v. The Netherlands on assessments of thethen-existing literature on effort-sharing methodologies in the IPCC’s AR4.5 It
recognized that in the absence of political decisions at the global level on
emission reductions which are sufficient to collectively lead to holding the
global temperature level below the appropriate level, it was for the courts to:“assess whether the measures taken by the State are too little in the view ofwhat is clearly the lower limit of its share in the measures to be takenworldwide against dangerous climate change.”6 The Procurator General of theSupreme Court in its Advisory Opinion recognised that such scientific studies
are not binding in and of themselves, nor provided “cut-and-dried answers.”7
However, given the assessment was derived from the latest scientific studies
and covered a “broad spectrum” of effort-sharing methodologies,8 it could be
IPCC, Climate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to
the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (“AR6 WGIII”),
Chapter 14, p. 1468 (link).
3
Ibid: “Equity and fairness concerns are being raised in national and regional courts that are
increasingly being asked to determine if the climate actions pledged by states are adequate in relation
to their fair share (The Supreme Court of the Netherlands 2019; European Court of Human Rights
2020; German Constitutional Court 2021), as it is only in relation to such a ‘fair share’ that theadequacy of a state’s contribution can be assessed in the context of a global collective action problem.”
4
Ibid.
5
The Hague District Court, Urgenda v. The Netherlands, ECLI:NL:RBDHA:2015:7196, 24 Jun. 2015
(link) and Dutch Supreme Court, Urgenda v. The Netherlands, ECLI:NL:HR:2019:2007, 20 Dec.
2019 (link).
6
Dutch Supreme Court, Urgenda v. The Netherlands (n 5), §6.3 (link).
7
Advisory Opinion on Cassation Appeal of the Procurator General in the Matter between the
Netherlands v Urgenda ECLI:NL:PHR:2019:1026, 13 Sept. 2019 §4.129-4.137 (link).
8
Ibid., §4.131.
2

6

considered a “reasoned proposal” that the Court was right to attach significanceto in specifying the State’s legal obligations under Arts. 2 and 8 ECHR.9
13

The German Federal Constitutional Court in Neubauer and Others v
Germany10 similarly engaged in a detailed manner with the science ofdetermining a country's “fair share.”11 The Court acknowledged that there areseveral scientific methods for determining a State’s necessary emissions
reductions to hold global warming to a particular temperature limit, all of which
entail uncertainties. Nevertheless, the Court found that:“this does not make it permissible under constitutional law for Germany’s required
contribution to be chosen arbitrarily. Nor can a specific constitutional obligation to
reduce CO2 emissions be invalidated by simply arguing that Germany’s share of the
reduction burden and of the global CO2 budget are impossible to determine.”12

The Court particularly emphasised the importance of the carbon budgets as
specified by the IPCC, stating that:“In view of the risk of irreversible climate change, the law must therefore take into
account the IPCC’s estimates on the size of the remaining global CO2 budget and its
consequences for remaining national emission budgets (...) if these point to a possibilityof exceeding the constitutionally relevant temperature limit.” 13

Based on a report on a national carbon budget by the German Advisory Council
on the Environment, the Court concluded that under the legislated reduction
targets, almost the entire carbon budget for Germany would be used up by
2030.14 On this basis, the Court held that:“the legislator has violated its duty, arising from the principle of proportionality, toensure that the reduction of CO2 emissions to the point of climate neutrality that isconstitutionally necessary under Art. 20a GG is spread out over time in a forwardlooking manner that respects fundamental rights.”15

14

The studies provided by the Applicants provide an appropriate common groundon which the Applicants’ request can be granted. Both the study of the Climate
Action Tracker (“CAT”), as well as the study of Rajamani et al.16 (Obs., §§41

Ibid., §§4.133 and 4.137.
BVerfG, Neubauer and Others v. Germany, 1 BvR 2656/18, 24 March 2021 (link).
11
Ibid., §222-225.
12
Ibid., §228
13
Ibid., §229
14
Ibid., §231.
15
Ibid., §243.
16
RAJAMANI ET AL., National ‘fair shares’ in reducing greenhouse gas emissions within the principledframework of international environmental law, Climate Policy 21:8, pp. 983–1004, 2021 (link) (Obs.,
910doc. 43)7f.) built upon the assessment of effort-sharing studies as reported by the IPCC
in its AR5, updated with more recent studies and historical data.17 They
therefore cover an even “broader spectrum” of effort-sharing methodologies ascompared to the AR4 assessment which served as the basis of the Dutch
Supreme Court’s judgement. In contrast, the Respondent has not provided any
quantified justification for the fairness of its emission target.
3.2. The “fair share” contribution requested by the Applicants does not put an
inequitable burden on the Respondent
15

First of all, the requested level of net-negative emissions by 2030 by the
Applicants is significantly less stringent than the result of the CAT and Rajamani
et al. study (i.e. a reduction between 160% and 200% by 2030 below 1990
levels, Obs., §§41 f.). Moreover, the effort-sharing studies put forward by the
Applicants only determine the “fair share” level of emission reductions for acountry, and not whether these reductions need to be achieved domestically.
Alleged technical difficulties and high costs of reducing emissions within the
Respondent’s territory are irrelevant to determine the level of responsibility foroverall emission reductions,18 which can also be achieved through supporting
countries with lower levels of responsibility and capability.19

16

The Respondent is well aware of this, as is evident from the fact that it
specifically plans to achieve its communicated goal of 50% reduction by 2030
compared to 1990 levels through purchasing emission reductions abroad (Obs.,§34). Given that the Respondent is one of the wealthiest States globally, it canCAT, CAT rating methodology, fair share (link), contains a full description of the methodology andi.a. states: “The effort-sharing studies in the CAT’s database include over 40 studies used by the 5thAssessment Report of the IPCC (chapter 6 of WG III, Höhne et al. (2013)), new studies that have been
published since, and additional analyses the CAT has performed to complete the dataset.” The
Supplementary material of Rajamani et al. mentions: “The literature database for national emission
levels based on effort sharing builds off that developed by Höhne et al (2014)and used in the IPCC
WGIII AR5 report (Clarke et al., 2014) and used in the Climate Action Tracker (Ganti et al., in prep)”(link).
18
RAJAMANI ET AL. (n 16), s2.3.1.
19
See IPCC, Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III
to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (“AR5 WGIII”),
Chapter 6, p. 457 (link): “A crucial consideration in the analysis of the aggregate economic costs ofmitigation is that the mitigation costs borne in a region can be separated from who pays those costs.
Under the assumption of efficient markets, effort-sharing schemes have the potential to yield a more
equitable cost distribution between countries.” Also, RAJAMANI ET AL. (n 16), s4: “Developed statesthat have high historic responsibility, high GDP per capita, etc. end up with a 1.8°C or 1.5°C consistentemissions level in 2030 that is around zero (USA, Japan) or net-negative (e.g. Germany, France, UK).
This means that these states have already used their fair share of emissions space and should stopemitting by 2030. If such a level is not reachable with domestic emission reductions, these states willneed to correspondingly scale up the support they offer to others to reduce their emissions, based on
the principle of cooperation.”
17

8

undoubtedly scale up its support to developing countries in the form of financeor other support for mitigation to reduce their emissions as part of its “fairshare” contribution. The Applicants stress that the Respondent has neverclaimed that it is not able to raise its ambition (Obs., §55).
3.3. The IPCC’s global emission reduction pathways are not “fair share” pathways
17

Contrary to the Respondent’s view, the IPCC global emission reduction
pathways cannot be used as indicators of fairness. This is explicitly recognisedby the IPCC itself, stating that most of the “global modelled emission pathways,(...) do not make explicit assumptions about global equity, environmental
justice or intra-regional income distribution.”20
18

The stark contrast between following a “fair share” or a global modelled
emission reductions pathway can be illustrated by the graphs below. In thesegraphs the methodology of following global modelled pathways put forward by
the Respondent is applied to Switzerland (with relatively high historic emissions
and large financial capacity) and India (with relatively low historic emissions
and low financial capacity). The current per capita CO2 emissions of
Switzerland in 2021 is 4.02 tonnes of CO221, compared to that of India whichis 1.93 tonnes of CO2.22 For determining their emission targets, both countries
start from their current level of emissions and follow the emission reduction
pathway towards zero from the IPCC global trajectories. The dashed area below
the curve shows the cumulative emissions emitted by each country from thecurrent day until 2050.

IPCC, Climate Change 2023: AR6 Synthesis Report (“AR6 SYR”), SPM Box SPM.1 (link).
Our World in Data based on the Global Carbon Project (2022) (link).
22
Ibid.
20
21

9

19

These graphs clearly show that the Respondent's approach of following global
modelled pathways, allows itself to cumulatively emit significantly more
greenhouse gases (“GHG”) per capita than India. This is because the current
share of global emissions also determines the future share of global emissions.
It is clear that the Respondent’s strategy that grandfathers past emissions andapplies constant emission ratios for future emissions cannot be considered a“fair share” of the global burden of mitigating climate change. This is also
recognised in the internal working document (see below, §57).

20

As clearly and convincingly set out by Rajamani et al., it is also in violation ofequitable principles of international environmental law:“(...) the pragmatic choices some states make in selecting their NDCs based on current
emissions levels (‘grandfathering’) and in charting an extended mitigation pathwaythat privileges current (high) levels, and may even maintain the current uneven
distribution of emissions across nations (‘constant emissions ratios’), finds nojustification in the equitable principles of international environmental law. Quite thecontrary. The principles of sustainable development, common but differentiatedresponsibilities, and equity, read in the light of the normative framework of the UN
climate treaties, recognize that current levels of emissions in some states are high(United Nations, 1992b, preambular recital 3) and in others emissions may need to
grow to achieve sustainable development, and eradicate poverty (United Nations,1992b, preambular recital 22, Art. 4.7; UNFCCC, 2015, preambular recital 8, andArticles 2.1 (chapeau), and 4.1). Grandfathering or maintaining constant emission
ratios arguably creates ‘cascading biases’ against poorer states (Kartha et al., 2018), is
not a ‘standard of equity’ (Dooley et al., 2021), and is indeed morally ‘perverse’(Caney, 2011). It is also a well-established principle of common law that no person
ought to profit from their own wrong (Dworkin, 1967). It is worth noting thatinternational legal accountability for historical emissions hinges on whether such
emissions were internationally wrongful acts at the time. However, selecting a shareof emissions reduction effort based on models that privilege current and past highlevels of emissions and that may even lead to a continuation of uneven shares is an
ongoing (not a historical) wrong.”23

23

RAJAMANI ET AL. (n 16), s2.3.1.

10

4.

Detailed reply to the Respondent’s written answers to the questions posed by
the Court

4.1. The Respondent did not approach the question of what level of climate
protection must be ensured to be in line with the 1.5°C limit with due
diligence
21

The Respondent alleges that the Swiss NDC “is based” on the Policy Brief andthe internal working document (Respondent, paras. 6 and 15). However, in its
letter handed to the Court on 12 April 2023, the Respondent (i.e. Mr. Franz
Perrez, Ambassadeur de la Suisse pour l’Environment, Chef de la Division desAffaires Internationales de l’Office fédéral de l’environnement) put it in a moremodest perspective: “The document provided is an internal study produced
independently by the ethics department of the Federal Office for theEnvironment, which does not reflect the views of the Swiss government.
Switzerland has taken this study into account in developing its climate target”(emphasis added). It should be noted here that the internal working document
does refer to a further document as a “basis for mitigation” called “Equity
Betrachtungen in der Klimazielsetzung” of the FOEN division of international
affairs. This document has not been provided by the Respondent, and theApplicants sought access to this document in their request dated 6 April 2023
(doc. 3).

22

The positive obligation to protect the Applicants effectively includes first andforemost establishing a legislative and administrative framework to do its shareto prevent a global temperature increase of more than 1.5°C above preindustrial levels (see e.g. Obs., §112). Furthermore, there are procedural
obligations or due diligence obligations with regard to how the Respondent has
to approach the question of what level of climate protection should be pursued
to be in line with the 1.5°C limit.

23

Under the Court’s case law, when a State has to deal with complex
environmental and economic policy issues, and in particular when dangerous
activities are involved, the decision-making process prior to establishing a
legislative and administrative framework must first involve the carrying out ofappropriate investigations and studies, to prevent and assess in advance theeffects of activities which may harm the environment and the rights of11

individuals.24 Also, the public must have access to the conclusions of suchstudies and to information enabling it to assess the danger to which it is
exposed.25 Furthermore, the decision-making must effectively take into accountthe outcome of the assessment so as not to deprive the procedural guarantees
of any useful effect. 26 This approach of the Court is supported by therequirements of Art. 4, 6 f. and 9 Aarhus Convention on Access to Information,
Public Participation in Decision-making and Access to Justice in Environmental
Matters (“Aarhus Convention”).27
24

As the Applicants stated in their Observations, the Respondent has not only
failed to establish a legislative and administrative framework to do its share toprevent a global temperature increase of more than 1.5°C above pre-industrial
levels. The Respondent has also failed to afford the Applicants the necessary
procedural guarantees or to approach the question of the necessary level ofclimate protection with due diligence.

25

Particularly, as the Applicants noted in their submissions, the Respondent has
never conducted any studies to find out what its “fair share” would be to limit
global warming to 1.5°C (Observations on the Facts of 13 October 2021, “OF”,§130 and Obs., §125). It should be emphasised that it was the FOEN that
confirmed this to the Applicants. To be more specific, on 19 February 2021,
based on the Freedom of Information Act, notably an important domestic
implementation of the Aarhus Convention,28 the Applicants requested accessto investigations and studies on which the level of climate protection is based(Obs., doc. 20). With a letter dated 10 March 2021, the FOEN stated thefollowing (Obs., doc. 21; own translation from the German original):“The FOEN has referenced and published all the documents used and taken into
account in the respective dispatches and in the long-term climate strategy. The
bibliographies of the long-term climate strategy for Switzerland and the dispatch on
the total revision of the CO2 Act after 2020 can be found in the annex. The studies
and research on which the current CO2 Act is based are also referenced in the Dispatch
on Swiss Climate Policy after 2012. The FOEN has not commissioned any further

See Tătar v. Romania, no. 67021/01, §88 and Taşkin and Others v. Turkey, no. 46117/99, §119.
See Tătar v. Romania, no. 67021/01, §88 and Taşkin and Others v. Turkey, no. 46117/99, §119.
26
See Taşkin and Others v. Turkey, no. 46117/99, §125.
27
In its previous case law, the Court has repeatedly referred to these requirements of the Aarhus
Convention, see Di Sarno and Others v. Italy, no. 30765/08, §107; Tătar v. Romania, no. 67021/01,§118; Taşkin and Others v. Turkey, no. 46117/99, §99.
28
Eidgenössischer Datenschutz- und Öffentlichkeitsbeauftragter (EDÖB), Aarhus Convention, last
updated 18 January 2023 (link).
24
25

12

investigations or studies or relied on any other non-referenced significant studies”(emphasis added).

26

Remarkably, the aforementioned bibliography (Obs., doc. 21) included various
documents somewhat related to climate change but did not include any
investigations or studies relating to the level of climate protection andimportantly, made no mention of the Policy Brief and the internal working

document. Indeed, neither the Policy Brief nor the internal working document
have been cited in any dispatch on Swiss climate policy to this date. 29
27

The Applicants note with great surprise that the Respondent has now pulled
the Policy Brief and the internal working document, notably dating from 2012
and 2020 respectively, out of the hat, without ever referring to them in theproceedings before this Court or in the national proceedings. The Respondentis alleging in its written answers in clear contrast to FOEN’s 2021 statementthat the level of climate protection would have been based on these documents(Respondent, para. 15), and later in F. Perrez’ letter to the Court, that these
documents have been taken into account in determining the level of climate
protection. At the same time as allegedly determining the level of climate
protection in Swiss policies, the Respondent nonetheless states that these
documents do not reflect the views of the Swiss government.

28

Regardless of the truth of the position, the Policy Brief and the internal working
document are insufficient to satisfy the procedural guarantees and due diligenceobligations (above §23) owed by the Respondent towards the Applicants. The
Respondent rightly does not claim otherwise.

29

First, the Respondent did not carry out any “appropriate” investigations or
studies, as will be shown in detail below (ss4.2–4.7). With regard to the “new”
material handed to the Court, it should be noted that the Policy Brief is a
general study about fair burden sharing “in a Dynamic World” and calculates
carbon budgets for “selected countries” (Policy Brief, s4.2), but not for
Switzerland. The internal working document on the other hand relates to
Switzerland but does not entail any quantitative assessment of Switzerland’s

Regarding the CO2-Act 2011, see Federal Gazette, BBl 2009 7433 (link); regarding the ratificationof the Paris Agreement, see Federal Gazette BBl 2017 317 (link); regarding the (later rejected) CO2Act 2020, see Federal Gazette, BBl 2018 247 (link); regarding the revision of the CO2-Act 2011 forthe time until 2024, see Federal Gazette, BBl 2021 2252 (link); regarding the revision of the CO2 Act
for the time after 2024, see Federal Gazette, BBl 2022 2651 (link); regarding the climate policy forthe time after 2030 until 2050, see Federal Gazette, BBl 2021 1972 (link), BBl 2022 1536 (link) andBBl 2022 1540 (link).
29

13

“fair share.” From this alone, it follows that neither document can beconsidered as an “appropriate” assessment of the necessary level of climate
protection.
30

Second, the Policy Brief and the internal working document have not (or only
partly) been made in advance, i.e. before decision-making. Important decisions
regarding the Swiss climate policy, particularly regarding the level of climate
protection by 2020 and by 2030, were taken from 2011 onwards.30

31

Third, the conclusions of the Policy Brief and the internal working document
have not been made available to the public by the Respondent in the context
of its decision-making process regarding the level of climate protection, evennot upon explicit request (see above §25 f.).
32

Fourth, the decision-making did not effectively take into account the Policy
Brief and the internal working document. This is clear from the fact that if the
Respondent had taken them effectively into account, Switzerland’s climate
policy would differ significantly from today's approach. For example, as madeclear by the Expert Report based on Switzerland's current and planned emission
reduction targets, the remaining 1.5°C Swiss budget that can be calculated on
the basis of Policy Brief’s methodology will already be depleted before
2030/2033.

33

Thus, had the Respondent applied the 2012 Policy Brief’s methodology to
Switzerland and implemented the results in its climate policy, Switzerland
would have had to adopt emissions targets that are significantly more stringent
than its current and planned targets (see above §9). Also, the internal working
document would have provided for a significantly different climate policy,
stating e.g. contrary to the current and planned Swiss climate policy – andindeed in line with the Applicants’ requests – that grandfathering does notprovide satisfying answers on how to distribute the burden of mitigating climatechange (internal working document, pp. 26–36), that the territorial approachneeds to be complemented by a consumption-based approach (internal working
document, p. 58), and that offsets (purchasing emission reductions abroad)cannot be used as a substitute to meeting its domestic target (internal working
document, p. 58). Lastly, the internal working document itself says that it is a

Regarding the CO2-Act 2011, see Federal Gazette, BBl 2009 7433 (link); regarding the ratificationof the Paris Agreement including approval of Switzerland’s 2015 NDC, see Federal Gazette BBl 2017317 (link); regarding the (later rejected) CO2-Act 2020 that has foreseen Switzerland's climate policy
until 2030, see Federal Gazette, BBl 2018 247 (link).
30

14

piece in the internal opinion forming process, but that, for taking decisions,

legal and political criteria would be decisive instead (internal working
document, p. 1).
34

Overall, the Respondent did not approach the question of what level of climate
protection must be ensured to be in line with the 1.5°C limit with due
diligence. The Respondent rightly does not allege otherwise.

35

Furthermore, the manner in which the Policy Brief and the internal working
document were withheld (notwithstanding the Applicants’ explicit request fordisclosure) and the contrast of the advice contained in the documents with the
Respondent’s claims to have it “taken into consideration”, both further
demonstrate why it is critically important for this Court to order generalmeasures under Art. 46 ECHR as requested by the Applicants (Obs., p. 70).

4.2. The decision-making process prior to establishing a legislative andadministrative framework did not involve the carrying out of “appropriate”
investigations and studies and consequently did not result in a “fair share”
contribution by Switzerland
36

In the following sections, the Applicants further substantiate that the
Respondent did not approach with due diligence the question of what level ofclimate protection must be ensured to be in line with the 1.5°C limit. First, theApplicants turn to the Respondent’s “qualitative assessment” of its “fair share”
and show that this “assessment” cannot be considered an “appropriate”
assessment of the necessary level of climate protection (s4.3). Second, theApplicants turn to the Respondent’s “quantitative assessment” of its “fairshare.” They show that the Respondent did not determine any national carbon
budget as a “fair share” of the remaining global budget (s4.4); that the allegedalignment of the Respondent with the IPCC global emission trajectories is not
appropriate and consequently did and will not result in a “fair share”
contribution by Switzerland (s4.5); and that the Respondent’s critique on theexpert studies put forward by the Applicants is superficial and unfounded(s4.6). Third, the Applicants show that the requested emission reductions do
not put an inequitable burden on the Respondent (s4.7).

37

Ultimately, the Respondent did develop a climate strategy that is not in linewith the 1.5°C limit. The Applicants showed this in detail in their Observations
and fully uphold these statements (see Obs., s1.10). Nothing has changed in15this respect as a result of the Respondent’s written answers. To the contrary,
the Policy Brief and the internal working document submitted by the
Respondent can only serve to validate the position of the Applicants.
4.3. Indicators of fairness put forward by the Respondent are not in line with
relevant principles, including those set out by the Respondent in its internal
working document
38

The Respondent sets out at paras. 7–11 of its written answers the three equity
considerations on which its NDC is allegedly based. These are responsibility(Respondent, para. 8), ability (Respondent, paras. 9 and 11), the “available
effective mitigation potential” and the costs of reducing emissions (Respondent,
para. 10). Furthermore, the Respondent alleges that its NDC is based on
analysis including the Policy Brief and the internal working document(Respondent, para. 15).

39

The Applicants first turn to the considerations on responsibility. The
Respondent states that, with a view to responsibility, total emissions must be
taken into account (Respondent, para. 8). However, a small share of global
emissions is not an indicator that is in line with principles of international
environmental law31 and thus cannot be taken into account to inform a State’s“fair share”32 (Obs., §41). Absolute emissions mainly relate to the size of thecountry. Notably, all countries with less than a 2% share of global emissions
represent in total 36% of global emissions, which is far from “negligible” andindeed more than e.g. China.33

40

The Respondent further refers to the indicator “per capita emissions.” Although
this indicator is not directly anchored in principles of international
environmental law, according to Rajamani et al., it arguably finds support inhuman rights instruments and approaches and is thus included in the results of
their study.34 Thus, while this indicator can be used to inform a State’s “fairshare”, the Respondent wrongly alleges that the Swiss “per capita emissions”

See hereto in detail RAJAMANI ET AL. (n 16), pp. 991 f., stating that “Principles of international
environmental law build on the understanding that the environment is a matter of ‘common concern’and that all states, ‘big and small’ (United Nations,1972, principle 24) ‘cooperate in a spirit of global
partnership’ to restore the environment (United Nations,1992a, principle 7). National court decisions
have also rejected the argument that a small share of emissions, whether from a mining project or astate, justifies continuation of those emissions or limits the action that needs to be taken (...).”
32
Ibid., p. 995.
33
RITCHIE, Why “my country only emits 1% of emissions” is no excuse for rich countries to not tackle
climate change, Sustainability by numbers, 11 March 2023 (link).
34
RAJAMANI ET AL. (n 16), p. 996.
31

16

would be below the global average and would “continue to decrease”(Respondent, para. 8). Notably, and decisive with a view to the Respondent’s
historic responsibility, from 1954 to 2013, the Swiss “per capita emissions”
have constantly been above the global average, and often to a significant extent
of about 50 to 70%.35 Indeed, the Respondent’s per capita emissions have been
increasing since 2020.36 Furthermore, when pointing to allegedly low “percapita emissions” today, the Respondent omits the significant share of external
emissions attributable to Switzerland, including consumption-based emissions(see hereto Obs., §§3 ff.). Notably, the Swiss per capita consumption-based
emissions are well over the average for EU countries (Obs., § 4), and from 1990
onwards constantly around three to four times higher than the global average.37
41

Besides that, it is notable that the Respondent’s understanding of responsibility
and its application in its NDC 202138 dismisses important considerations madein its internal working document. For example, the internal working documentfinds that the State is responsible to pay poorer countries for mitigation
measures without counting them towards its own obligation of domestic
emission reductions (internal working document, pp. 41f. and p. 58). It
explicitly holds that it is not justified to buy your way out of responsibility andthat Art. 6 Paris Agreement (“PA”) should not be used for that purpose either(internal working document, p. 58). Rather, the internal working document
states that the territorial measurement of GHG emission should be
supplemented by a consumption-based view, to take into account the wholecarbon footprint (internal working document, p. 58).

42

Concerning the Respondent's considerations on ability, the parties agree thatthe indicator gross domestic product (“GDP”) per capita is consistent with theprinciples of environmental law and thus has to be taken into account when
determining its “fair share” (Respondent, para. 9).39 The parties agree that
Switzerland has an extremely high GDP per capita (Respondent, para. 11).
Remarkably, Switzerland has the third largest GDP per capita in the world.40

Our World in Data, Per capita CO2 emissions, Switzerland and World (link).
FOEN, Kenngrössen zur Entwicklung der Treibhausgasemissionen in der Schweiz, 1990–2021,
April 2023, p. 39 (link).
37
Our World in Data, Per capita consumption-based CO2 emissions, Switzerland and World (link).
38
Switzerland’s information necessary for clarity, transparency and understanding in accordance withdecision 1/CP.21 of its updated and enhanced Nationally Determined Contribution (“NDC 2021”)
under the Paris Agreement (2021-2030), 17 Dec. 2021 (link) (Obs., doc. 46).
39
RAJAMANI ET AL. (n 16), p. 996.
40
Statista, Die 20 Länder mit dem grössten Bruttoinlandsprodukt (BIP) pro Kopf im Jahr 2021, October
2022 (link).
35
36

17

The internal working document rightly makes clear that the wealthier a Stateis, the larger has to be its contribution to burden sharing (internal working
document, p. 45), and that rich countries like Switzerland must do much moreto support poorer countries (internal working document, p. 57). However,there is no evidence whatsoever that the Respondent took all this into accountin both determining and quantifying its allegedly “fair share” – but there isplenty of evidence that it did not do so.
43

The Applicants lastly turn to the Respondent’s allegation that the “available
effective mitigation potential” and “the costs of reducing emissions” as well as“past efforts” (Respondent, paras. 10 f.) have to be taken into account. Cost
efficiency is not an indicator that is supported by the equity principles ofinternational environmental law and thus not an indicator that can be used todetermine the Respondent’s “fair share” (Obs., §41). 41 As explained in theabove (s3.2) technical difficulties and high costs of reducing emissions within
its territory are irrelevant to determine the level of responsibility for overall
emission reductions, which can also be achieved through supporting countries
with lower levels of responsibility and capability.

44

Moreover as is confirmed by the Respondent’s internal working document,
wealthy States have to implement the lowest-emission technologies in theireconomies, even if this is associated with higher costs (internal working
document, p. 47), which is why cost-efficiency (and rewarding allegedly earlymovers) are not relevant considerations in determining a State’s “fair share”(internal working document, p. 57).

45

That said, least-cost pathways are relevant in determining the minimum levelof the domestic emission reduction component of a State’s “fair share.”42 As
will be further discussed below, if a country were to reduce its emissions at alower rate than its modelled domestic pathway that is derived from the IPCC
global pathways, other countries would need to cut emissions faster to maintain
1.5°C compatibility (§§77 f.). In other words, if Switzerland reduces its
domestic emission by less than the requested “more than 60%” by 2030
compared to 1990 (Obs., §§ 45ff.), not only would this gap in emissions
reductions need to be compensated by other countries; the additional emission

See RAJAMANI ET AL. (n 16), pp. 991 f.
Compare also RAJAMANI ET AL. (n 16), p. 992, stating that “identifying a least cost pathway may be
a relevant consideration in choosing between alternative means of implementing national fair shares,
it is not a relevant consideration in determining fair shares.”
41
42

18

reduction measures that would have to be taken in this scenario would
generally also be more expensive than if Switzerland had taken those measuresitself (Obs., §46). Moreover, given that these modelled domestic pathways aretechnically and economically feasible (Obs., §46) they disprove the assertion of
the Respondent that it would not be able to achieve this level of more than 60%
emission reductions by 2030 compared to 1990 domestically (Obs., §55).
46

Further, the Respondent does not provide any evidence for its claim that there
would be only limited availability of cost-effective mitigation potential in the
short term (Respondent, para. 11). The Applicants submit that this is wrong(see hereto Obs., §§ 45 ff. and 53, and OF, §§118–123). It should be reiterated
that there are important GHG-relevant sectors including cost-effective
mitigation potential which are not regulated and used, e.g. in the agriculture
and finance sector (Obs., §53; OF, §123). Also, the potential for reducing
emissions in the building and transport sectors is being severely under-used andthe available measures were insufficiently enforced (Obs., §53; OF, §122 withfurther references). Precisely because these sectors are characterised by longprocessing periods, it is all the more important to take immediate action to
avoid a lock-in of carbon-intensive infrastructure.

4.4. The Respondent did not determine any national carbon budget as a “fairshare” of the remaining global budget
47

The Respondent alleges that Switzerland has adopted a national climate policythat “comes close to a budgetary approach” (Respondent, paras. 1 and 2).

4.4.1.
48

No overall national budget has been adopted in relation to the global
emissions budget

The Respondent did not adopt an overall quantitative national emissions budget
in relation to the global 1.5°C emissions budget. By setting emission reduction
targets, the Respondent has merely defined an approximate budget of emissions
that it allows itself. The Respondent has admittedly not developed any
quantitative assessment of its national carbon budget, let alone a budget that
could be considered fair, in relation to the global budget. Doing so would
require first determining the portion which can be seen as the “fair share”, as
was done in its “own” Policy Brief (but not for Switzerland). In a purely “equal
per capita” methodology, this share would be equal to the share of Switzerland
in the global population (cf. Obs., §38). This share would then be applied to19the available global budget to determine a national budget. Emission targets
would then need to be set such that the resulting total cumulative emissions
over time do not exceed the defined budget. It is clear from all evidence that
the Respondent did not conduct any quantitative assessment of its nationalemissions budget to that effect.
4.4.2.
49

The Respondent’s “budgetary approach” leads to a completely inadequate“national budget”

Even by applying a simple “equal per capita” approach from 2020 onwards,
under its current climate strategy, the Respondent will have used up its
remaining budget by 2034 (Obs., §38). From this alone it is clear that the
Respondent’s “budgetary approach” is arbitrary, leading to a completely
inadequate “national budget.” If all countries were to set their budgets in thismanner, the available global budget would be far exceeded.

4.4.3.
50

What if the Respondent adopted a national budget based on the Policy
Brief?

The Expert Report applied the methodology of the Policy Brief to the remaining
global 1.5°C budget from the IPCC’s AR6 and calculated that following
Switzerland's current and planned emission reduction targets, Switzerland’sbudget would be depleted before 2030/2033 (Expert Report, Figures B and C).
For Switzerland to stay within the budget as defined by the methodology of its
own Policy Brief, it would need to achieve net-zero emissions by 2040, andthus well before its current target of net-zero by 2050 (Expert Report, FigureA).

51

It should be noted that the Expert Report indicates several shortcomings in themethodology in the Policy Brief. For example, the Policy Brief approach gives
higher shares to countries that historically have higher per capita emissions, thecapabilities of countries do not affect their “fair share”, and it focuses on the
inclusion of costs, technological feasibility and political acceptance (Expert
Report, s3). The Expert Report notes that as such, the approach in the Policy
Brief is not appropriate to determine Switzerland's “fair share” emission
reduction target in line with the PA temperature limit that can be met throughboth domestic emission reductions and international support (Expert Report,
s6).

20

52

The Expert Report’s critique of the Policy Brief illustrates how a principled
analysis of the quantification of a country's “fair share”, as done by Rajamani etal., can assist in defining “fair shares” in line with a country’s legal obligations(rather than political convenience). It also shows that choices on the weighingof indicators influence the results of individual studies. As is further explained
below (s4.6), contrary to the Respondent, the Applicants do not rely on a single
paper which applies a single set of assumptions on the weighing of indicators.
In contrast to the study in the Policy Brief, the studies from the CAT and
Rajamai et al. are each assessements of more than 30 individual studies that all
apply their own assumptions. These assessment studies determine their results
based on all the interpretations of fairness in the academic literature giving eachcategory of interpretation equal weight, and thus represent the scientific“common ground” as assessed by the best available science.

4.5. The alleged alignment of the Respondent with the IPCC global emission
trajectories did and will not result in a “fair share” contribution by
Switzerland
4.5.1.
53

The development of NDC in 2015 based on global (and thus not “fair”)
pathways and with a view to the now outdated 2°C limit

The Respondent states that it developed its NDC in 2015 based on AR5. It
alleges that AR5 “recommended” a reduction of GHGs of 40 to 70% by 2050
compared to 2010 levels, but that Switzerland has committed to more
ambitious targets, i.e. minus 50% by 2030 and 70–85% by 2050 (Respondent,
para. 2).

54

The Applicants submit that the Respondent’s reference relates to the global
trajectories defined in AR543 and that the Respondent’s strategy was to roughly
follow this global trajectory.

55

As explained above, the IPCC has been explicit in its reports that global
trajectories cannot be used to determine a country's “fair share” (s3.3). On thecontrary, in its AR5, the IPCC provided various trajectories based on different
burden-sharing methods (cf. Obs., § 32). Significantly, for a 66% likelihood of
the now outdated 2°C temperature limit not being exceeded, the IPCC

IPCC: Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to theFifth Assessment Report of the Intergovernmental Panel on Climate Change (“AR5 SYR”), p. 20 (link).
43

21

concluded that to reflect responsibility,44 capability45 and need,46 OECD
countries such as Switzerland needed to meet negative emissions targets; they
had to reduce emissions by between – 106% and up to – 128% below 1990
levels by 2030.47
56

Following the global trajectory is not consistent with the equitable principles ofinternational environmental law (e.g. the principle of common but
differentiated responsibilities and respective capabilities, in the light of different
national circumstances “CBDRRC-NC”, Art. 4(3) PA, Art. 3(1) and 4(1)UNFCCC, Principle 7 Rio Declaration 48).

57

First, as shown above, by taking the current level of emissions as a starting
point, a State’s historic responsibility for past emissions is ignored (s3.3). Thismethodology effectively means that States with higher current emissions (likethe Respondent) are afforded higher future emission allowances. This is“grandfathering.”49 This is recognised in the Respondent’s internal working
document which states that grandfathering is “not plausible” (internal working
document, p. 14) and does “not give a satisfying answer” to the question of
how to distribute the burden of mitigating climate change (internal working
document, pp. 26–36).

58

Secondly, the global emissions pathways presented by the IPCC generally
describe emissions pathways that are most cost-efficient at a global level.50
Taking such cost-efficiency considerations as the basis for an individual
country’s overall emission reductions is not supported by principles ofinternational law51 and does not entail any considerations of equity and
CBDRRC-NC which are central principles of the international climate treaty
regime. The Applicants further refer to their Observations (Obs., §§37 ff.).

IPCC, Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to
the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (“AR5 WGIII”), p. 458(link): “The concept to use historical emissions to derive emission goals was first directly proposed by
Brazil in the run-up of the Kyoto negotiations (UNFCCC, 1997), without allocations. Allowances based
only on this principle were quantified by only a few studies.”
45
Ibid.: “Frequently used for allocation relating reduction goals or reduction costs to GDP or humandevelopment index (HDI). This includes also approaches that are focused exclusively on basic needs.”
46
Ibid.: “A multitude of studies provide allocations based on immediate or converging per capita
emissions.”
47
Ibid., p. 460 figure 6.28, p. 13 table SPM.1. Note that fig. 6.28 of p. 460 states in its explanation:“For the OECD-1990 in the category ‘responsibility, capability, need’ the emission allowances in 2030
is – 106% to – 128% (20th to 80th percentile) below 2010 level (therefore not shown here).”48
See RAJAMANI ET AL. (n 16), p. 990.
49
Ibid., p. 992.
50
IPCC, AR6 SYR (n 20), SPM Box SPM.1
51
RAJAMANI ET AL. (n 16), s2.3.
44

22

4.5.2.

The alleged reassessment of NDC in 2020 was merely a formal update
and did not make it “fair”

59

The Respondent alleges that it reassessed its 2015 NDC following the IPCC’s
Special Report on the impacts of global warming of 1.5°C (“1.5°C SR”) with aview to the new global emission reductions trajectories therein (Respondent,
paras. 4 f.).

60

However, the Respondent’s “update” of its 2030 emissions reduction target in
the NDC did not represent a “progression,” as required by, for example,
Art. 4(3) PA, but was no more than a formality (Obs., §34).

61

Furthermore, following the global cost-efficient trajectories cannot be
considered as “fair” and is not in line with equitable principles of international
environmental law (s3.3). What a 1.5°C compatible “fair share” contributionof the Respondent looks like is set out by the Applicants in their Observations(Obs., s1.10.1).

4.5.3.
62

The alleged planned reassessment of NDC in 2025 is unlikely to takeplace and to make it “fair”

The Respondent subsequently refers to the IPCC’s AR6 and the thereinmodelled global pathway with a possibility of over 50% of limiting warming to
1.5°C, requiring a reduction in net global GHG emissions from 2019 levels of
43% by 2030 and by 85% by 205052 (Respondent, para. 4). The Respondent
alleges that the Swiss 2030 climate target would be in line with this global
pathway and for 2050, it would go even further, thus respecting the“encouragement of the Paris Agreement that developed countries should
continue to take the lead” (Respondent, para. 5). The Respondent then goes on
to allege that it will take the “latest findings” of the AR6 into account whensetting a new emission reduction target, to be communicated in 2025
(Respondent, para. 5).

63

The Applicants assume against this background that the Respondent plan, totake “the latest findings” into account, relates to the IPCC AR6 Synthesis Report
finalised in March 2023.53 The Synthesis report, however, does not have any
different modelled global reduction trajectories than those in the IPCC’s AR6
WGIII report. Thus, if the Respondent takes global trajectories of the Synthesis

52
53

See IPCC, AR6 WGIII (n 2), SPM C.1.1.
IPCC, AR6 SYR (n 20).

23

Report as the foundation for deciding whether to increase its climate targets (asrequired by, for example Art. 4(3) PA), it is clear that the Respondent will not
set new emission reduction targets at the next round of NDC submissions. The
Respondent also does not provide any evidence for its alleged reassessment. On
the contrary – the Respondent’s public communication, e.g. in recent
dispatches, leaves no doubt that if the 2030, 2040 and 2050 targets are
accepted by the Parliament or the Swiss people, this is the way to go in the
future.54
64

Moreover, following an emissions reduction pathway that is marginally more
ambitious than the global cost-efficient trajectory (that is not a “fair share”
pathway, see above s3.3) cannot be considered to be in line with the obligationof “taking the lead” (Obs., §§ 37 and 141).

65

The Respondent’s climate policy is not even aligned with global cost-efficient
trajectories: Climate Analytics as well as CAT scaled down the global costeffective emission pathway to the level of Switzerland and thereby derived adomestic emissions reduction of more than 60% by 2030 (see Obs., § 46),
which stands in stark contrast to the envisaged domestic reduction of –34% by
2030 (see Obs., §34).

66

While a reassessment of Switzerland’s NDC or its national climate targets isunlikely, it would be even less likely that this reassessment would result in a
Swiss climate strategy that is in line with the 1.5°C limit as requested by the
Applicants (Obs., ss1.10, 2.5 and 3).

67

Lastly, the Applicants stress that there is no time to wait until 2025 to set new
emission reduction targets. The longer the Respondent waits to start cutting its
emissions in line with its “fair share”, the faster it will eventually have to cut
emissions to make up for lost time and stay within its “fair share” budget (seeExpert Report, Figure D). Such increasingly steeper emission reductions will
become progressively more difficult to achieve (Obs., §47).

That there has to be a periodic review of the climate targets is only mentioned in theoretical terms.
See e.g. Federal Gazette, BBl 2022 2651 section 1.1.2 (link) “Contexte international” and section 1.2“Nécessité d’agir at objectifs” and BBl 2022 1536 section 1.4 (link) stating “Parallèlement, le présent
contre-projet indirect à l’initiative pour les glaciers doit définir le cadre des prochaines révisions de laloi sur le CO2 et marquer l’ambition de la politique climatique de la Suisse ” (highlights added) andsection 2.1 “L’art. 11, al. 1, de la loi-cadre oblige le Conseil fédéral à soumettre suffisamment tôt àl’Assemblée fédérale, après avoir entendu les milieux concernés et en tenant compte des dernières
connaissances scientifiques, des propositions de mise en œuvre des objectifs de la loi pour les périodes
suivantes…” (emphasis added).
54

24

4.6. The Respondent’s critique of expert studies is superficial and unfounded
68

The Respondent alleges throughout its written answers that there is no agreed
methodology for calculating “fair shares” or for allocating the global carbon
budget to individual States (Respondent, paras. 1, 3, 6, 14, 15). In this context
the Respondent argues that the studies put forward by the Applicants contain“strong elements of subjectivity” and have several shortcomings. As will beshown in detail, this critique is superficial and unfounded.

4.6.1.
69

No agreed methodology for calculating “fair shares”

As demonstrated above (s3.1), while there is no set mechanism on what
constitutes a fair level of contribution (Obs., §39), it is still possible and, theApplicants submit, necessary for the Court to assess–

70

whether the Respondent’s climate strategy is in line with 1.5°C (Obs.,s1.10) and thus in line with its obligations to protect the Applicants’
Convention rights, and, if not,– to determine what that obligation should be (Obs., s2.5).
For example, the apex Courts of the Netherlands and Germany have illustrated
that national emission reduction efforts are within the scope of judicial scrutiny(see above §§12 f.). Drawing on established principles and norms ofinternational environmental law and the scientific consensus, various national
courts have assessed the lawfulness of a State’s mitigation efforts and, in somecases, determined absolute minimum GHG emissions reduction efforts that arenecessary to protect human rights (see Obs., footnote 414).

71

Notably, the scope of the Respondent’s obligation to protect is determined interalia by the precautionary principle (Obs., s2.5.4). The precautionary principle
has been invoked by many national courts in their deliberations on theappropriate level of action for a State to take in climate cases (Obs., §147 andfootnote 327). In particular, the precautionary principle supports the position
that any ambiguity as to the necessary emissions reductions to prevent a global
temperature increase of more than 1.5°C should be resolved in favour of the
Applicants (Obs., §149). Also, the Applicants submit that with a view to theprecautionary principle, there is no discretion regarding the emissions
reductions necessary to do its share (Obs., §134); in any case not to the extent
that the discretion goes beyond the emission reductions requested by the
Applicants. This is because the requested “fair share” contribution of net25

negative emissions in 2030 is even significantly lower than the scientific“common ground” as assessed by best available science, i.e. the IPCC, CAT,
Climate Analytics and Rajamani et al. (cf. speech for the oral hearing,55 §51).
Lastly, it should be noted that the approach of drawing on other norms ofinternational law to determine the content of a State’s “fair share” – as adopted
by the Rajamani et. al. study – is consistent with this Court’s harmonious
interpretation of the Convention (Obs., §41 and s2.5.4). It is also in line with
the Recommendation CM/Rec(2022)20 of the Committee of Ministers
adopted on 27 September 2022, stating in the Appendix that“the member States should ensure the respect of general principles of international
environmental law, such as the no harm principle, the principle of prevention, theprinciple of precaution and the polluter pays principle, and take into account the needfor intergenerational equity.”56

72

Overall, the fact that there is no agreed methodology for calculating “fairshares” is no justification for the Respondent failing to protect the Applicants
effectively (Obs., s2.5.1.3). As the IPCC noted, it is only in relation to a “fairshare” that the adequacy of a State’s contribution can be assessed.57 Contrary
to the Respondent (Respondent, para. 13), the onus is on the Respondent tojustify its climate strategy, using detailed and rigorous data (Obs., §125), which
the Respondent has not done. On the contrary, even the methodology from theonly study put forward by the Respondent which quantifies national “fairshares” shows that the Respondent’s emission targets are grossly insufficient tocontribute towards holding global warming below the 1.5°C limit.

4.6.2.
73

Critique of the CAT and Climate Analytics Studies

In its written answers the Respondent argues that the studies from the CAT(Obs., docs. 19 and 44) as well as the study by Climate Analytics: A 1.5°C
compatible Switzerland (Obs., doc. 41), contain “strong elements ofsubjectivity” and have several shortcomings (Respondent, paras. 14–16 and18).

Speech for the oral hearing of 29 March 2023 (link).
Committee of Ministers, Recommendation CM/Rec(2022)20 to member States on human rights
and the protection of the environment, 27 September 2022 (link).
57
IPCC, AR6 WGIII (n 2), p. 1468.
55
56

26

74

Both CAT and Climate Analytics publish extensively on the methodologies that
underpin their studies.58 The Applicants respectfully submit that the
Respondent’s critique in no way engages with any element of themethodologies of the studies and that most if not all of its critique is addressedin the methodological descriptions. To assist the Court in evaluating the critiqueof the Respondent to the fullest extent possible, the Applicants requested
Climate Analytics and the CAT consortium to provide a detailed response oneach element of the critique for the attention of the Court, what they both did
with a letter dated 26 April 2023 each: response by Climate Analytics,
represented by Prof. Dr. Carl-Friedrich Schleussner (“CA response”, doc. 4) and
response by Prof. Dr. Niklas Höhne, NewClimate Institute and Bill Hare, CEO
Climate Analytics, acting on behalf of the CAT consortium (“CAT response”,
doc. 5). It is worth mentioning that Prof. Dr. Niklas Höhne was the main authorof the sections on effort-sharing in both AR4 and AR5.

75

The CA and CAT responses (including the explanatory context of the
Applicants’ questions to CAT and Climate Analytics) form an integral part ofthis submission. In addition to what is stated in the CA and CAT responses, inthe following paragraphs the Applicants will address the critique that thestudies contain “strong elements of subjectivity.”76

As the Respondent points out, the CAT on its website acknowledges that no
single equity framework has been agreed upon at the international level. The
academic literature however has set out the different ways in which equity
principles can be operationalised into national reduction targets. The IPCC in
AR4 and AR5 provided results on an assessment of the entire scope ofinterpretations proposed in the literature. The CAT has taken the AR5
assessment and its underlying database of studies as a starting point and updates
its findings on a continuous basis, with recent studies and emissions data (CATresponse, p. 2). Each of the individual studies that make up the entire databaseused by the CAT applies its “own” normative assumptions. Different from these
individual studies however, the CAT applies an equal weighting to all thedifferent categories of fairness principles. Thus, it considers all normativeinterpretations equally. As explained in the CAT response, this equal weighting

A full description of the methodology of the CAT analysis is published here; the detailed descriptionof the methodology to determine countries fair share is published here; the detailed description of themethodology to determine a countries nessesary domestic reductions is published here; themethodology for calculation domestic pathways in the Climate Analytics report is published here.
58

27

is “to avoid favouring any particular equity principle over another, as well as todevelop the most thorough equity framework possible in line with the best
available science” (CAT response, p. 2) and “developing a synthesis frameworkof all relevant equity approaches based on the best available science is the mostobjective way of establishing a state’s fair share of the global effort” (CATresponse, p. 3).
77

In further defining the required level of emission reductions for each country
the CAT applies an “equal level of ambition” for all countries within the range
of fairness interpretations from the literature (CAT response, p. 3). If all
countries were to “cherry pick” the equity interpretation most preferable to it,
the temperature target would be missed by a significant margin (CAT response,p. 2). By applying an equal level of ambition, no country is treated differently,
while still accounting for all the different interpretations of fairness. The
Applicants submit that, based on the precautionary principle, the results froman assessment that weighs all interpretations of fairness equally and applies anequal level of ambition within the range of fairness interpretations, such as is
the case in the CAT, provides an adequate basis for the determination of whatmust be perceived as the minimum level of protection that is required of the
Respondent. Accepting any lower level of protection would inevitably either
come at the cost of other countries or lead to the breaching of the temperature
limit.

78

The assertion of subjectivity by the Respondent concerning the Climate
Analytics report “A 1.5°C compatible Switzerland” is equally unfounded.
Rather than applying “different” assumptions than the IPCC for determining
the appropriate level of domestic emission reductions, the report uses as its baseall the models from the IPCC that are compatible with holding the temperature
increase below the 1.5°C limit and downscales these to the country levels (CATresponse, p. 4). The report thus does not apply its “own” assumptions but uses
the same “robust” assumptions as applied by the IPCC. Contrary to the
Respondent’s assertion (Respondent, para. 16), Climate Analytics provides astatistical range for the modelled domestic pathways, which the Applicants
explicitly mentioned in their Observations (Obs., §46). The median of that
range describes the minimum reduction level a country needs to achieve
domestically for it to be in line with the 1.5°C temperature limit. For
Switzerland this minimum is a reduction of more than 60% by 2030 compared28

to 1990 levels. As is further explained in the CAT response, a lower emission
reduction by Switzerland would necessitate faster reductions for othercountries (CAT response, p. 5). Given that these modelled pathways are basedon cost-effective considerations these higher recutions by other countries
would presumably also be more expensive (CAT response, p. 5).
4.6.3.
79

Critique of the Rajamani et al. study

With regard to the study by Rajamani et al., the Respondent alleges that the
principles of international environmental law are interpreted in a “subjectiveway”, whereas the content and legal status of these principles vary and would
be open to a range of interpretations. The Respondent further dismisses
Rajamani et al.’s exclusion of the principles of “small share of global emissions”
and “cost efficiency” as not adequately reflecting the specific situation of
Switzerland (Respondent, para. 17).

80

The Applicants submit the Respondent has a wrong understanding of Rajamani
et al. study. The interdisciplinary study led by Prof. Rajamani, notably
Coordinating Lead Author of the AR6 chapter 14 on International Cooperation,
alongside a team of leading climate scientists proceeds on the basis that there
is “no single accepted definition of the term” “fair share.”59 Its criticalcontribution, however, is to identify “principled limits” to the determination of
a State’s “fair share,” which it does in a transparent manner on the basis ofwell-established principles and norms of international law.60 The Rajamani etal. study first identifies principles and norms of international law that inform aState’s “fair share.” This includes the principles of sustainable development,
common but differentiated responsibilities and respective capabilities, andequity. These principles are not randomly selected but rather derive fromwidely-subscribed-to international instruments, including the UNFCCC and theParis Agreement. The study further confirms the relevance of these principles
to the issue of “fair share” by showing how States themselves invoke theseprinciples to justify the fairness of their contributions in their NDCs.61 On thebasis of these principles, the Rajamani et al. study excludes certain indicatorsthat States invoke to justify the fairness of their NDCs – i.e. “small share of

RAJAMANI ET AL. (n 16), p. 984.
Ibid.
61
The study assesses all NDCs submitted as of 31 December 2020 (168 NDCs in total) to identify
explicit and implicit references to these principles and norms.
59
60

29

global emissions” and “least cost.”62 Far from being purely subjective, the study
makes clear why these indicators are not consistent with principles ofinternational law and refers to national jurisprudence to date.
81

The second step in the study is to further narrow the “fair share” range forindividual countries by reference to the principles of harm prevention (which
is binding customary international law63) and precaution, in addition to thenormative pillars of the Paris Agreement (its objectives; the expectation ofprogression and “highest possible ambition”; and human rights). As is describedin the CAT response, the methodology of quantitatively determining the fairshare emission reductions of individual countries applies the same approach as
CAT, drawing from the full spectrum of equity perspectives provided in thescientific literature.64

82

The particular focus of the Rajamani et al. study is to analyse the broad
spectrum of effort-sharing methodologies through the spectrum of theprinciples framework of international law and that focus makes this study
particularly suitable to inform the Respondent’s obligation to protect under the
ECHR that is determined by the harmonious interpretation of the Convention(Obs., §41 and s2.5.4).

4.6.4.

The costs of reducing emissions within a few years would be very high83

The Respondent alleges the costs for achieving net negative emissions by 2030
would be very high or at least disproportionate given the modest effect of
Switzerland’s small contribution to global emissions (Respondent, paras. 16 and
17).

84

Climate Analytics and CAT explain (CA response, p. 2 f. and CAT response,p. 5), as did the Applicants in their Observations (§§44 and 55), that the “fairshare” contribution does not have to be achieved in full domestically (withmeasures taken within its own borders), but also with contributions toemissions reductions abroad and support for developing countries being able to

RAJAMANI ET AL. (n 16), pp. 991 f.
See: Legality of the Threat or Use of Nuclear Weapons, Advisory Opinion [1996] ICJ Reports 226(ICJ); Case concerning the Gabcikovo-Nagymaros Project (Hungary v Slovakia) [1997] ICJ Reports 7(ICJ); Case concerning Pulp Mills on the River Uruguay (Argentina v Uruguay) (2010) 2010 ICJ
Reports 14; Certain activities carried out by Nicaragua in the border area and Construction of a roadin Costa Rica along the San Juan River (2015) 665 ICJ Reports (ICJ).
64
A full description of the methodology of the RAJAMANI ET AL. (n 16) study is published in the
supplementary materials, available here.
62
63

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count towards this level of contribution. The Respondent thus seems tomisinterpret the results of Climate Analytics, CAT and Rajamani et al.
4.6.5.
85“Not all” qualitative assessments of equity can be translated intoquantitative results

The Respondent alleges that “not all” qualitative assessments of equity can betranslated into quantitative results, and that the results have their limitations(Respondent, para. 17).

86

It remains unclear what conclusions the Respondent draws from this in termsof its “fair share.” Although limitations of effort-sharing analysis are recognised,
this does not mean that the Respondent can discharge itself of its positive
obligations to do its “fair share” to limit global warming to 1.5°C.

87Furthermore, the IPCC in its AR4 and AR5, CAT and Rajamani et al. haveprovided quantitative results of their “fair share” assessments (see Obs., §§31,
32, and 40–42), based on qualitative assessments undertaken as a first step.
Thus, qualitative assessments can indeed be translated into quantitative results,
which is, in principle, also accepted by the Respondent.

4.6.6.
88

The studies put forward by the Applicants provide the best available
science to inform the scope of the Respondent’s obligation to protect

The scope of the obligation to protect is inter alia informed by the best available
science (Obs., §141). To the knowledge of the Applicants the recent
assessments on the range of fair level of contribution as provided by the
Applicants are the only available studies that provide a synthesised assessment
based on the full spectrum of effort sharing interpretations and thus present thescientific “common ground” as assessed by best available science (see above§§14 and 52).

89

The Respondent rightly does not allege otherwise; notably, it did not offer any
other or “better” science.

4.7. The requested emission reductions can be achieved by the Respondent
4.7.1.
90

The Respondent fails to meet its own (inadequate) climate targets andemissions are going up

The Respondent is alleging that Switzerland's emission reductions were “on aclear trajectory to achieve zero net emissions by 2050” (Respondent, para. 5).
31

91

However, the Respondent missed its 2020 target (Obs., §52), and the latest
emission data published 11 April 2023 are showing that emissions are not going
down, but up:“En 2021, la Suisse a émis 45,2 millions de tonnes d’équivalents CO2 (éq.- CO2), soit
1,3 million de plus qu’en 2020. Dans l’ensemble, les émissions étaient 18,2 %inférieures à leur niveau de 1990. Ces chiffres s’appuient sur l’inventaire de l’OFEV
sur les gaz à effet de serre. La plus forte hausse a été enregistrée dans le secteur dubâtiment, en raison des besoins de chauffage accrus liés à la rigueur de l’hiver. Lesémissions dues aux transports ont, elles aussi, légèrement augmenté. Celles dessecteurs de l’industrie et de l’agriculture sont quant à elles restées inchangées dansl’ensemble. S’agissant des gaz synthétiques, la tendance légèrement baissière observée
ces dernières années se poursuit.”65

4.7.2.

92

The Respondent’s ability to meet its NDC and its commitments under
the Paris Agreement pursuant to the available and planned climate
mitigation measures

The Respondent simply claims that with the proposed measures, emissions will
be reduced by 50% in 2030 compared to 1990, of which 34% will be achieved
domestically, and that it is thus taking the necessary steps to meet its NDC. The
Respondent goes on to state that it does not share the view of CAT and CA thatthe negative outcome of the June 2021 referendum would make it significantly
more difficult to achieve the objectives set (Respondent, para. 20), and that theFederal Council has given itself the means to achieve its NDC (Respondent,
para. 19).

93

The Applicants submit that the Respondent neither provides any evidence forits claim that the proposed measures will result in the reduction of domestic
emissions by 34% by 2030 compared to 1990 levels, nor does it explain why itdoes not agree with the outcome of CAT’s and CA’s assessment.

94

In its public communication, the Respondent itself conceded that the reduction
path to 2024 will not be sufficient to achieve Switzerland’s NDC; thatcompensating for the delay in emissions reduction will be a major challenge
and the share of measures taken abroad will have to be significantly higher thanplanned (Obs., §34 and footnote 81). In the context of the proposed 2030
target, however, the Respondent does not explain how the mentioned delay
could be counteracted. Instead, it refers to technological progress that

65

FOEN, Légère hausse des émissions de gaz à effet de serre en 2021, 11 April 2023 (link).

32

admittedly entails clear uncertainties (Obs., §34 and footnotes 85–87), and the(planned) emission reduction measures for 2030 which remain largely similar
to the ones in the extant CO2 Act 2011 (Obs., §54).
95

However, in purely arithmetical terms, the Respondent has secured theachievement of the overall (not domestic) 2030 NDC target by allowing itself
to flexibly choose the share of domestic reduction (Obs., §34), with the aim ofpurchasing carbon credits from other countries to the extent necessary, to claimthat it has made the necessary reductions (Obs., §54).

96

It should be noted that with regard to the planned 2040 and 2050 targets, theRespondent does not allege that it is able to meet these with the proposed
measures (Respondent, para. 21).

97

Clearly, and irrespective of the 2021 referendum, with its current and planned
climate strategy, the Respondent is not able to meet its commitment in the Paris
Agreement to limit global warming to 1.5°C (Obs., s.1.10), neither in terms of
its “fair share”, nor in terms of its domestic emission reduction pathway. The
Respondent rightly does not allege otherwise.

5.

Request for expert hearing98

During the hearing on 29 March 2023, the Applicants invited the Court toconsider holding an expert hearing particularly relating to the questions posedby the Court to the parties by letter of 16 March 2023.

99

The Applicants are aware that the questions on “fair share” and “carbon
budget” raise legal questions which are based on complex technical matters. If
the Court comes to the view that some issues remain unclear despite thissubmission and its annexes, the Applicants respectfully invite the Court to holdan expert hearing on these issues.

33

Zurich, London and Lausanne, 27 April 2023
Yours faithfully,

Cordelia Christiane Bährlic. iur., LL.M. Public Law (LSE),
Attorney-at-Law

Martin Looser
Attorney-at-Law

Jessica Simor KC

Marc Willers KC

Raphaël Mahaim, Dr. iur.,
Avocat34

Verein KlimaSeniorinnen and Others v Switzerland (Application no. 53600/20)
Table of content of the annexes to the submission to the ECtHR of 27 April 2023
Doc. 1:Doc. 2:

Respondent’s written answers with paragraph numbers added(“written answers”)
Dr. Yann Robiou du Pont and Dr. Zebedee Nicholls, “Calculation ofan emissions budget for Switzerland based on Bretschger’s (2012)
methodology,” 26 April 2023 (“Expert Report”)

Doc. 3:

Request to FOEN for access to official documents, 6 April 2023

Doc. 4:

Response by Climate Analytics, represented by Prof. Dr. CarlFriedrich Schleussner, 26 April 2023 (“CA response”)

Doc. 5:

Response by Prof. Dr. Niklas Höhne, NewClimate Institute and BillHare, CEO Climate Analytics, acting on behalf of the CAT
consortium, 26 April 2023 (“CAT response”)

35