The Paris Agreement on Climate Change: A Subtle Combination of

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The Paris Agreement on Climate Change: A Subtle

Combination of Tools and Actors for Better

Enforcement?

Mathilde Hautereau-Boutonnet, Sandrine Maljean-Dubois

To cite this version:

Mathilde Hautereau-Boutonnet, Sandrine Maljean-Dubois. The Paris Agreement on Climate Change:

A Subtle Combination of Tools and Actors for Better Enforcement?. Environmental Policy and Law,

2022, 52, pp.389 - 398. �10.3233/epl-219045�. �halshs-03919012�

The Paris Agreement on Climate Change: A Subtle Combination of Tools and Actors for

Better Enforcement?

Avec Mathilde Hautereau-Boutonnet, Environmental Policy and Law, 52 (2022) pp. 389-398.

https://content.iospress.com/download/environmental-policy-and-law/epl219045?id=environmental-

policy-and-law%2Fepl219045

The Paris Agreement on climate change:

a subtle combination of tools and actors for better enforcement?

Mathilde HAUTEREAU-BOUTONNET

Professor at Aix-Marseille University,

DICE, CERIC, Aix-en-Provence, France

Sandrine MALJEAN-DUBOIS

CNRS Research Director,

Aix-Marseille University, DICE, CERIC, Aix-en-Provence, France

(*)

Abstract: The Paris Climate Agreement can be seen as illustrating the evolution of how legal norms are enforced in

international law. While the Agreement benefits from a carefully thought-out enforcement mechanism in the

international legal order, with techniques that encourage compliance rather than sanction non-compliance, its

enforcement is also supported by domestic legal orders. Indeed, the Paris Agreement benefits from both hard and soft

enforcement mechanisms. Here, all techniques and all actors have a role to play. This contribution shows that in order

to discern the enforcement mechanisms attached to a legal instrument, it is sometimes necessary to take a global and

complex look at all legal orders, techniques and actors, since they can act in a complementary manner.

The international climate regime as we know it today is the outcome of a lengthy process

that started in 1988 with the establishment of an expert body, the Intergovernmental Panel on

Climate Change (IPCC). In 1992, States then developed a specific international legal regime,

based on the United Nations Framework Convention on Climate Change (UNFCCC, 1992). With

197 contracting parties, the Convention lays down a general framework for cooperation. It

determines the fundamental principles thereof and creates an institutional framework, including an

annual meeting of the Parties, the COP. In 1997, the Kyoto Protocol set out concrete obligations

for the reduction of greenhouse gas emissions relative to 1990 levels, but only for industrialised

countries. Initially, these obligations were only imposed until 2012; after tough negotiations, the

Protocol was extended for a second period which expired at the end of 2020. The regime applicable

from 2021 onwards is determined by the Paris Agreement and COP decision 1/CP.21 (which adopts

and supplements the Agreement), both adopted on 12 December 2015 at the end of COP 21.

The Paris Agreement elicits mixed feelings. On the one hand, it is a real diplomatic success.

With 193 parties today, it is already having an effect. A large number of countries have passed

legislation to implement it.

Furthermore, when the US under Donald Trump withdrew from the

treaty, it did not have the anticipated domino effect.

On the contrary, it has led the other States

Parties to reaffirm their will to implement the Agreement. Many even claimed that the Agreement’s

(*)

This contribution is based on our chapter: “La garantie normative de l’Accord de Paris sur le climat de 2015,” in Catherine

Thibierge (ed.) (2021), La garantie normative. Exploration d’une notion-fonction, Mare et Martin, Paris, 223-240.

See the definition of international regimes by S. Krasner (1983), International regimes, Cornell University Press, London, 2.

See the online database made by the Sabin Center/Columbia School of Law and the Grantham Research Institute on Climate

Change and the Environment, https://climate.law.columbia.edu/content/climate-change-laws-world (last accessed 6 May 2022).

J. Watts (2017), World leaders react after Trump rejects Paris climate deal, The Guardian, 2 June.

implementation should be “irreversible” (at COP 22, during G20 summits, etc.).

The American

withdrawal became effective on 4 November 2020, but one of the first decisions of Trump’s

successor Joe Biden, at the beginning of 2021, was to re-join the Agreement.

On the other hand, its provisions reveal real weaknesses. Indeed, the Parties’ commitments

may seem rather limited. The Agreement contains few substantive obligations and essentially

procedural ones. Each Party must make a nationally determined contribution, with no external

control over its content and level of ambition. While it must communicate this contribution to the

Secretariat and update it regularly – always upwards –, it is entirely free to decide on its substance.

Moreover, even though the Agreement provides that “Parties shall pursue domestic mitigation

measures, with the aim of achieving the objectives of such contributions” (Art. 4(2)), it does not

impose a specific result in terms of greenhouse gas emission reductions. If a State fails to comply,

no sanctions are provided for; the architects of the Agreement chose to focus on incentives instead.

Indeed, even six years after its adoption, the temperature limitation target set in the Agreement is

still completely unrealistic based on our emissions’ trajectories. This is established annually by the

United Nations Environment Programme in its report entitled The Emissions Gap, which is released

before each COP.

The latest report, published in 2021, estimates that even if the Parties’

contributions are all taken together, they do not come close to 2°C, but rather 2.7°C. This is

undoubtedly progress compared to the 4 or 5 °C expected by so-called “business-as-usual”

scenarios, but we are still very far from the objective set out in the Paris Agreement and, perhaps

even more importantly, from the safe operating range of our planet.

Nonetheless, the Agreement’s enforcement mechanisms were thought out and designed in

a subtle way, and are rather innovative. Nothing was left to chance, as both the adoption and

implementation of the Agreement depended on it. It was impossible to set up an international

judicial review mechanism. This would have deterred many States from ratifying the Agreement.

But it was necessary to include enforcement techniques. This was especially important as the

States’ commitments are nationally determined. Enforcing these commitments therefore

constitutes the main purpose of the Agreement.

The enforcement of the Paris Agreement relies on a plurality of methods and actors. On the

one hand, the current proliferation of climate proceedings in various domestic legal orders shows

that judicial review of compliance (potentially leading to sanctions) is likely to play a key role in

the enforcement of the Paris Agreement. “Hard enforcement” is very much a reality. On the other

hand, while the architects of the Agreement excluded coercion and sanctions in the international

legal order, they did not leave the Agreement without means of international enforcement. The

absence of “hard enforcement” is counterbalanced by the introduction of “soft enforcement”

mechanisms: the combination of a lack of judicial control and of an incentive and invitation to

comply. Indeed, as well as developing sophisticated techniques to encourage the Parties to comply,

the Agreement’s architects created an opportunity for non-parties to the Agreement to give effect

to the norm. Thus, the enforcement of the Paris Agreement relies on a multiplicity of techniques

under international and national law. Certain techniques existing in domestic orders enable courts

to ensure compliance with the Agreement by ordering sanctions in the event of non-compliance,

thereby addressing the limitations of the international legal order; other techniques set out in the

Agreement itself, and in some cases already in use within domestic orders, are designed to ensure

compliance with the Agreement without judicial control and sanction, by encouraging and inviting

compliance and by accompanying States that experience difficulties towards a return to

compliance. As a result, in order to be fully understood and appreciated, the enforcement of the

Paris Agreement invites us to reflect on the multiple ways this enforcement can be carried out, by

adopting a view that is both global – across legal orders - and complex – through the combination

See for instance https://unfccc.int/news/g20-leaders-says-paris-agreement-is-irreversible (last accessed 22 January 2022).

UNEP (2021), Emissions Gap Report 2021, The heat is on. A world of climate promises not yet delivered, Executive

Summary, IV.

W. Steffen et al (2015), Planetary Boundaries: Guiding human development on a changing planet, Science 13 Feb 2015,

Vol. 347, Issue 6223, 1.

of techniques. Enforcement of the Paris Agreement combines, in a very complementary manner,

both hard and soft mechanisms. We will demonstrate here that while hard enforcement is

essentially the result of a de facto transfer from the international legal order to domestic orders (I),

soft enforcement rests on a convergence of the international and domestic orders (II).

I. THE DE FACTO TRANSFER OF THE PARIS AGREEMENT’S HARD ENFORCEMENT

INTO DOMESTIC ORDERS

While the international legal order provides limited opportunities for enforcing the Paris

Agreement through judicial review, this could take place at the domestic level. Domestic orders,

through the intervention of the judge, can be seen here as a remedy for the weaknesses of the

enforcement mechanisms of the international legal order.

1. The limits of hard enforcement mechanisms in the international legal order

In theory at least, the Paris Agreement can give rise to the intervention of a judge or an

arbitral tribunal in the event of a dispute between two or more States Parties regarding its

application or interpretation. In Article 14, the Agreement refers to the dispute settlement clause

included in the 1992 United Nations Framework Convention on Climate Change. It states that “The

provisions of Article 14 of the Convention on settlement of disputes shall apply mutatis mutandis

to this Agreement” (Art. 24). Article 14(1) of the UNFCCC provides that the Parties must

endeavour to settle their disputes by diplomatic means. If this fails, Article 14(2) contains an

optional clause for judicial and arbitrational settlement: the Parties may declare in advance that

they accept the submission of disputes to the International Court of Justice or to an arbitral tribunal.

This mechanism could in theory be activated in response to a violation of the Convention,

especially as notions such as an injured State or “a dispute between any two or more Parties

concerning the interpretation or application of the Convention” (and thus of the Agreement) should

in this instance be understood quite broadly. The heart of the Agreement, which consists of

obligations and tools to reduce emissions, presumably falls into the category of erga omnes partes

obligations, ie they are owed to all parties to the treaty. Several Pacific Island States actually

specified when ratifying the Agreement that their ratification did not constitute a waiver of the

liability of other States under international law for the adverse effects of climate change. But in

practice, because it is optional, this clause can hardly come into play. Indeed, it has not been very

successful: of the 197 parties to the Framework Convention, only the Netherlands has accepted the

jurisdiction of the International Court of Justice and the use of arbitration, while the Solomon

Islands and Tuvalu have accepted the compulsory arbitration of Article 14(2). Because of the

requirement for reciprocity, this clause could therefore only come into play to support arbitration

proceedings between the Netherlands and Tuvalu or the Solomon Islands, or between Tuvalu and

the Solomon Islands.

Theoretically, there could be other possible bases for the jurisdiction of an international

court or arbitral tribunal, such as a bilateral or multilateral dispute settlement treaty providing for

such jurisdiction.

Two parties to a dispute may also accept such jurisdiction after such dispute has

arisen. However, judicial intervention remains highly unlikely, as legal obstacles are coupled with

the political reluctance of States. In any event, no dispute has been submitted to the ICJ or to an

arbitral tribunal pursuant to the UNFCCC and, to our knowledge, this has never been seriously

considered, despite the fact that many heated disputes have arisen. If the ICJ or the International

Tribunal for the Law of the Sea intervene, it will probably be through advisory proceedings first,

rather than a contentious case. Thus, there are real limits to the hard enforcement mechanisms of

See the American Treaty on Pacific Settlement (Pact of Bogota), 30 April 1948, United Nations Treaty Collection, 1949,

85.

the Agreement in the international legal order. They are therefore complemented by the

possibilities for hard enforcement in domestic orders. Indeed, as the “regular” judge of whether

international law is complied with internally, the domestic judge is bound to play a particularly

important role here in the context of the contagious explosion of climate lawsuits.

2. The possibilities for hard enforcement in domestic legal orders

Within internal orders, each State organises how compliance with internally applicable

norms is reviewed. Once the Paris Agreement (or for dualist legal systems, the law transposing its

content) is applicable and can be relied on in domestic courts, interested parties have several

possibilities for enforcing these norms. Right away – through legal proceedings, trials and their

outcomes – domestic courts are able to make up for the weaknesses inherent in the international

legal order. This is what the hundreds of climate-related lawsuits taking place around the world

already suggest. Around 2,300 climate-related lawsuits have been tried or are pending, and this

number is still growing.

While they rely on many different grounds, and excluding those against

companies, these lawsuits share a common goal: they challenge the lack of ambition of a State’s

climate policy and seek to force it to adopt measures to combat climate change. Climate change

litigation challenging the behaviour of States – but also companies – in the face of climate change

did exist in the United States and Australia before the Paris Agreement was adopted. However, the

Agreement has been like an electric shock, leading to an increase in litigation beyond US borders.

Thanks to the involvement of civil society, it has provided fuel for climate litigation in a decisive

manner and offered national courts the opportunity to position themselves as key players of climate

governance.

Legal action has also been brought by cities, NGOs, groups of citizens (American children

from Our Children’s Trust, Swiss senior women, a law student from New-Zealand, etc.) against

major corporations whose activities are allegedly causing global warming. Globalised and

transnational, these proceedings in some respects break down national borders.

Faced with what

is perceived as a failure on the part of public authorities or companies, the law is increasingly relied

on and used as a “weapon” to serve various objectives: to encourage public authorities or

companies to take stronger measures to mitigate climate change, to implement more ambitious

policies, to obtain compensation for damage suffered, to stop a project that emits large quantities

of greenhouse gas, etc.

The way it was designed, and even though its provisions have no or little direct effect, the

Paris Agreement increases the pressure on States, including, and perhaps most importantly, at the

domestic level. Indeed, the Agreement, in its design, combines the international definition of an

ambitious collective goal of limiting global warming with an implementation tool, referred to as

the nationally determined contributions, the content, form and scope of which are almost entirely

up to the Parties, to whom a very wide discretion is thus given. What could be analysed as a

congenital weakness of the Agreement has actually “boosted” climate litigation and allowed

claimants to define effective legal strategies.

Although the provisions of the Paris Agreement are

only one of the elements invoked amongst other rules of international law, the Agreement is

generally at the heart of arguments as well as decisions. It is almost always the entry point for other

rules of international law. The combination of international climate law rules and international

human rights law rules is, for instance, increasingly invoked.

Courts are then asked to read the

States’ obligations regarding the protection of human rights in the light of their climate obligations,

See the Sabin Center Climate Change Litigation databases http://climatecasechart.com/climate-change-litigation/ (accessed

6 May 2022).

See for instance “German court paves way for Peruvian farmer’s suit against RWE,” Reuters, 30 November 2017.

D. Estrin (2016), “Limiting Dangerous Climate Change: The Critical Role of Citizen Suits and Domestic Courts - Despite

the Paris Agreement,” CIGI Papers, N°101, 2016, 5.

J. Peel, H. Osofsky (2018), “A Rights Turn in Climate Change Litigation?,” Transnational Environmental Law, 7(1) 37-

67.

whether in a national court,

or before international human rights protection bodies such as the

United Nations Committee on the Rights of the Child

or the European Court of Human Rights.

The Urgenda case demonstrated a particularly synergistic interpretation of a combination of

customary norms (the Dutch duty of care or no harm rule), treaty rules under international human

rights law, together with the objectives and principles of the UNFCCC.

This combination can be

found in most similar cases, such as in Belgium, with Klimaatzaak, currently pending before the

Brussels Court of Appeal, where the Court of First Instance found that there had been violations of

Articles 2 and 8 of the European Convention on Human Rights, read in the light of the duty of care

of the good family father (or the reasonable man in Common Law), a standard itself informed by

the Paris Agreement.

It was also the case in France, with the "Case of the century". Here, in the

light of international law (the UNFCCC and Paris Agreement), European Union law (the Climate

and Energy Package) and domestic constitutional provisions (Article 3, Environmental Charter),

the administrative judge decided that the State had accepted a “general obligation to combat climate

change” and, more precisely, to reduce their greenhouse gas emissions.

In climate trials, international law is rarely applied directly, as a source of positive law,

either because the legal system is dualist, or because the obligations in question are not viewed as

self-executing and therefore cannot be directly invoked by individuals. However, the Paris

Agreement, alone or in combination with other international obligations, has been successfully

used in many cases to interpret domestic rules. The French climate case Commune de Grande

Synthe v. France is a good illustration. The judge found that “Although the stipulations of the

UNFCCC and the Paris Agreement (...) require the intervention of additional acts to produce effects

with regard to individuals and are, therefore, devoid of direct effect, they must nevertheless be

taken into consideration in the interpretation of the provisions of national law, in particular those

(...), which, referring to the objectives that they set, are precisely intended to implement them.”

In this instance, the court carries out a systemic interpretation (domestic law “in the light of,”

including all of the relevant legal elements, but also factual or even moral elements), a teleological

interpretation (the aim is to limit temperatures as decided in the Paris Agreement) and/or an

extensive interpretation. It has more discretion in its assessment of whether it is appropriate to use

international law, as well as in the choice of sources relied on, which may include unratified treaties

or soft law instruments. Indeed, as an interpretative source, the international norm becomes

subsidiary, as it is not the implementation of the Paris Agreement that the claimants are asking for,

but that national policies implement the country’s international commitments or conform to a

consensual standard of conduct.

The monist or dualist nature of the legal system thus becomes

irrelevant.

II. THE CONVERGENCE OF SOFT ENFORCEMENT MECHANISMS IN THE DOMESTIC

AND INTERNATIONAL ORDERS

See Urgenda, Supreme Court of the Netherlands, ECLI:NL:HR:2019:2007, Hoge Raad, 20-12-2019, para. 5.6.2.

Petition before the Committee on the Rights of the Child on 23 September 2019, Chiara Sacchi et al. v. Argentina, Brazil,

France, Germany, Turkey. Decision adopted by the Committee on the Rights of the Child under the Optional Protocol to the

Convention on the Rights of the Child on a communications procedure in respect of Communication No. 106/2019, 21 September

2021.

With pending cases involving Portuguese youth, Swiss elders or an Austrian with temperature-dependent multiple sclerosis.

O.W Pedersen, The European Convention of Human Rights and Climate Change - Finally! https://www.ejiltalk.org/the-european-

convention-of-human-rights-and-climate-change-finally/ September 22, 2020 (last accessed 23 May 2022).

Urgenda, Supreme Court of the Netherlands, abovementioned, para. 5.7.5.

See their main conclusions, http://climatecasechart.com/climate-change-litigation/wp-content/uploads/sites/16/non-us-

case-documents/2019/20190628_2660_na.pdf (last accessed 23 May 2022).

Paris Administrative Court, France, 3 Feb. 2021, No. 1904967, 1904968, 1904972, 1904976.

http://climatecasechart.com/wp-content/uploads/sites/16/non-us-case-documents/2021/20210203_NA_decision-1.pdf (last

accessed 23 May 2022).

Council of State, France, 19 Nov. 2020, No. 427301. http://climatecasechart.com/wp-content/uploads/sites/16/non-us-case-

documents/2020/20201119_Not-Yet-Available_decision-2.pdf (last accessed 23 May 2022).

K. Bouwer, “The Unsexy Future of Climate Change Litigation”, Journal of Environmental Law, 2018/30(3) 492.

In order to ensure the implementation of the Agreement through non-judicial means and

without resorting to sanctions, and thus to make up for the fact that hard enforcement is almost

impossible at the international level, the Agreement’s architects paid greater attention to soft

enforcement techniques. Here we see a sophistication of techniques. Contrary to hard enforcement

mechanisms which are unified around judges and sanctions, soft enforcement mechanisms rely on

a wide range of techniques and feature a variety of actors. In the international legal order, they

encourage the Parties to comply with the Agreement; in the domestic orders, they invite non-parties

to do so.

1. Soft enforcement by way of encouraging the Parties in the international legal order

Provisions ensuring transparency and control are all the more important in a flexible system

where contributions are determined by States themselves. The enhanced transparency framework

has been referred to as the "beating heart" of the Paris Agreement.

It reintroduces more or less

top-down aspects into an approach that is predominantly bottom-up. Importantly, it also creates

trust between the States Parties, which has a positive impact on their willingness to increase their

commitments. It also makes it possible to monitor the Parties’ efforts, and to compare them with

the target emissions trajectory. Negotiators were well aware of this and special care was dedicated

to this matter on which a great part of the robustness of the Agreement depended.

As regards transparency and control, the Paris Agreement merely lays down key principles

in its articles 13 to 15. The Agreement outlines a process that respects state sovereignty but equally

ensures the accountability of States. This procedure takes the form of a triptych composed of three

- more or less distinct - parts: the transparency framework (Art. 13), the global stocktake (Art. 14),

and the implementation and compliance mechanism (Art. 15).

In Article 13, the Agreement establishes an “enhanced transparency framework for action

and support”. However, while being referred to as “enhanced”, this framework is also characterised

by “built-in flexibility which takes into account Parties’ different capacities” (Art.13(1) and 13(2)).

It is specifically stated that this framework must be implemented “in a facilitative, non-intrusive,

non-punitive manner, respectful of national sovereignty, and avoid placing an undue burden on

Parties.” Apart from these assertions designed to reassure the Parties, the transparency framework

is based on an established system, i.e. the mechanisms, procedures, and obligations that exist under

the Convention (Art. 13(4)). Article 13(5) goes on to give a “clear understanding” of the measures,

“including clarity and tracking of progress towards achieving Parties’ individual nationally

determined contributions.” This also applies to financial support measures, both received and

provided, which means that information can be cross-checked here as well to provide a “clear

understanding” (Art. 13(6)). The Parties are required (“shall”) to “regularly” provide a national

inventory report on anthropogenic emissions by sources and removals by sinks of greenhouse

gases, prepared in accordance with the methodologies adopted by IPCC, and the information

necessary to monitor progress in the implementation of their nationally determined contribution

pursuant to article 4. In contrast, the Parties “should”, rather than “shall”, provide information on

the support provided and received, especially as to whether it is “financial, technology transfer and

capacity-building support” (Art. 13(9) and (10)).

An interesting feature is that this information is subject to a “technical expert review”. This

technical phase is followed by a political phase of “facilitative, multilateral consideration of

progress” (Art. 13(11)). The technical review must “identify areas of improvement for the Party”

(Art. 13(12)), which is in fact an understatement to refer to potential or actual infringements. The

review assesses whether the information provided is consistent with the modalities, procedures and

guidelines that will be established by the meeting of the Parties to the Agreement.

Support is

L. Rajamani, J. Werksman (2021), “Climate Change,” Oxford Handbook of International Environmental Law, OUP, Oxford

505.

C. Voigt (2016), “The Compliance and Implementation Mechanism of the Paris Agreement,” RECIEL 25 (2) 161-173.

See Decision 1/CP.21 (2015), para. 93.

provided to developing countries to assist them in the implementation of these provisions. Here the

Northern countries lobbied – especially against the preferences of China and of many Southern

countries – for the transparency system to be the same for all. Thus, even though this system focuses

on facilitation, the outlined mechanism seems to be relatively intrusive for all. While it remains to

be seen what operational details will be adopted by the meeting of the Parties, it currently seems

that the system’s individual nature, the wide range of information it requires as well as the dual

intervention of an independent and impartial technical committee and the subsequent handover to

a political body, possibly the COP, for the purpose of a multilateral review, will not make the

system less intrusive for the time being.

The transparency framework, which consists of the individual review of the implementation

of the Agreement by the Parties, is supplemented by the “global stocktake” contemplated in Article

14. The aim of this global stocktake is to assess the “collective progress”, “in a comprehensive and

facilitative manner, considering mitigation, adaptation and the means of implementation and

support, and in the light of equity and the best available science” (Art. 14(1)). The first global

stocktake will take place without waiting for the end of the first cycle, in 2023, and, subsequently,

every five years. Yet, the States have taken further precautions. The assessment of this achieved

collective progress will be facilitative (i.e. non-binding); it will take into account “equity and the

best available science.” The reference to equity may leave the door open to a collective reflection

as to the modalities of “burden sharing” in the light of the “common but differentiated”

responsibilities of States in this regard.

The global stocktake, which covers mitigation and adaptation efforts as well as support

measures, will play a significant role as “the outcome of the global stocktake shall inform Parties

in updating and enhancing, in a nationally determined manner, their actions and support in

accordance with the relevant provisions of this Agreement, as well as in enhancing international

cooperation for climate action” (Art. 14(3)). This provision is evidently very carefully drafted. On

the one hand, it clearly provides that the results of the stocktake will inform the determination of

States’ contributions. But on the other hand, it highlights that these are to be determined at national

level. It should also be noted that the objectives as regards adaptation, finance or technology are,

at least in the Agreement itself, qualitative rather than quantitative in nature, which introduces a

degree of uncertainty in the assessment of collective progress.

The third component to ensure transparency is the non-compliance mechanism. This kind

of mechanism is very common in international environmental law and its effectiveness has been

demonstrated on numerous occasions in the past.

Apart from a number of common features, each

procedure is ultimately unique. It will differ in terms of how it is initiated, the handling of presumed

infringements or the reaction to a proven infringement. What is however common to all of these

procedures, is that they aim to identify the challenges faced by States as early as possible and to

address them through gradual and adapted means (support, incentives, sanctions). They tend to be

facilitative and rarely lead to sanctions, which are generally counterproductive anyway. The goal

is rather to prevent non-compliance and when it occurs, to assist States back to compliance.

Pursuant to the Kyoto Protocol, a very intrusive procedure had been put in place that could lead to

relatively hefty sanctions.

Praised as a remarkable innovation at the time, it also swiftly revealed

its limits. In fact, Canada used its right to leave the Protocol in order to avoid its sanction under

this procedure.

Since States apparently learned the lesson from this experience, and because the spirit of

the Paris Agreement is very different from that of the Kyoto Protocol, the procedure chosen here

is much more traditional. All the precautions were taken to prevent the Implementation and

Compliance Committee from sanctioning a non-complying State. But this approach is not without

criticism. It has been condemned as one of the great weaknesses of the Agreement by several

See for instance, M. Koskenniemi (1992), “Breach of Treaty or Non-Compliance? Reflections on the Enforcement of the

Montreal Protocol,” Yearbook of International Environmental Law, Volume 3, Issue 1, 123.

See Decision 27/CMP.1 (2005), Procedures and mechanisms relating to compliance under the Kyoto protocol.

commentators.

In fact, this weakness goes beyond the Paris Agreement and is frequently observed

in international law. The absence of sanctions in the Paris Agreement, at the end of the day, shows

that lessons have been learned from the past. Since the spirit of the Paris Agreement is utterly

different from the Kyoto Protocol, arguably sanctions would have been incompatible with the

former. Beyond that, the question arises as to whether the effectiveness of international law

depends solely on the ability to sanction non-compliance. In fact, in our view, it generally does not

depend on it at all.

2. Soft enforcement by way of inviting non-parties to comply in internal orders

Soft enforcement by way of inviting non-parties to comply with the Agreement was also

carefully thought out by the Agreement’s architects. While welcoming “the efforts of all non-Party

stakeholders to address and respond to climate change, including those of civil society, the private

sector, financial institutions, cities and other subnational authorities” (para. 133), the COP 21

decision that adopts and specifies the Agreement “Invites the non-Party stakeholders (...) above to

scale up their efforts and support actions to reduce emissions and/or to build resilience and decrease

vulnerability to the adverse effects of climate change and demonstrate these efforts via the Non-

State Actor Zone for Climate Action platform” (para. 134), a network created at the instigation of

France, Peru and the UN Secretary General on the occasion of COP 20 in Lima. Thus, in a novel

way, assuming that the actions of these non-parties can converge with the objectives set by the

Agreement and/or the national contributions, the Paris Agreement invites them to take action.

Therefore, the enforcement of the Paris Agreement could be underpinned in an original way by the

actions within domestic orders of actors not directly targeted by the Agreement.

Like the limits on hard enforcement by way of sanctions in the international legal order and

the preference for soft enforcement by way of incentive, enforcement by way of invitation stems

here from a realistic and pragmatic view of the conditions governing the effectiveness of the

Agreement. On the one hand, non-parties – in particular sub-state actors (cities, regions, federated

states, etc.) and private actors (companies and investors) – can and do play an important role in the

fight against climate change. They are the addressees of the internal norms adopted by States to

implement their international commitments, but they can also take action of their own accord and

do more through voluntary initiatives, ie a variety of voluntary commitments (adherence to

greenhouse gas emission accounting systems, commitments to increase their reduction, etc.) which

are seen today as the normative manifestations of corporate social responsibility.

Given the risk

that States might not comply with the Agreement and because we know that, taken all together,

States’ contributions are not enough to achieve the objective of limiting temperatures as set out in

the Agreement,

it is therefore appropriate to mobilise these actors. On the other hand, they are

not parties to the Agreement and therefore cannot be directly targeted by its provisions. The drafters

could not impose on them obligations that could be sanctioned in the event of non-compliance, nor

procedural obligations of transparency that would ultimately allow their measures to be monitored.

It is therefore understandable that they chose to “invite” them to act by promoting their initiatives.

While leaving them free to act as they wish, the Agreement again relies on transparency to make

their actions visible. However, this technique is not as “proceduralised” as it is for States Parties.

No monitoring system exists at the moment, although the UN Secretary General announced the

creation of a high-level expert group for this purpose during COP 26.

Nonetheless, the reality is that initiatives have consistently increased since the adoption of

the Paris Agreement. They also grew strongly following the announcement of the US withdrawal

from the Paris Agreement. They are spreading under the impetus of networks bringing together

regions, cities and federal states, and private actors such as companies and – increasingly –

For instance, D. Gros (2015), The Paris Agreement Is the Shove the World Needs, Slate, 14 December 2015.

G. De Lassus Saint-Geniès (2016), “À la recherche d’un droit transnational des changements climatiques,” 1 Revue

juridique de l’environnement, 81 and following.

See UNEP (2021), Emissions Gap Report 2021, The heat is on. A world of climate promises not yet delivered,

abovementioned.

investors, as in the case of organisations like C40 Cities, R20, Greenhouse Gas Protocol, WE

MEAN BUSINESS, Institutional Investors Group on Climate Change (IIGCC) or WE ARE STILL

IN. As highlighted by some authors,

these actors aim not only to help their members strengthen

their climate efforts by encouraging the sharing of information on best available techniques for

reducing and accounting for GHG emissions, but also to connect them with investors to support

their energy transition.

Thus, day after day, non-parties are becoming key actors in giving effect to the Paris

Agreement. They do so in two different ways: on the one hand, through their initiatives, they enable

States Parties to fulfil their main obligation, which is to take measures to achieve the objectives of

their national contribution. Here non-parties are contributing to the implementation of the

Agreement. On the other hand, these initiatives can also be seen as a response to the failure of the

Parties to the Agreement. Thus, the WE ARE STILL IN network intends to implement the

objectives of the Paris Agreement through the initiatives of its members. In this case, these

initiatives are a “substitute” for States who are failing to fulfil their obligations. It is no longer a

question of collaborating with the State to help it meet its obligations, but to fulfil them in its place.

However, since they cannot be parties to an international agreement, these actors only play the role

of ‘guarantor’ by voluntarily implementing a key instrument that is not directly addressed to them.

Of course, like all the above-mentioned enforcement techniques, the effectiveness of this

“invitation” remains conditional. It depends both on what domestic law imposes on these actors

and on the added value of the measures that the latter adopt beyond that, without constraints.

However, upon examination, domestic law can already play an important role, through the

intervention of lawmakers as well as the courts. It calls for better voluntary commitments and the

combination of soft and hard enforcement mechanisms.

On the one hand, it is worth noting that some countries, including members of the European

Union, have adopted environmental reporting systems pursuant to which a number of large

companies are required to disclose to shareholders and the public certain non-financial information

about their climate commitments.

Companies are thus encouraged to take action in order to

protect their good reputation on the market, to reassure investors and shareholders and to avoid

legal sanctions in case of non-compliance. Furthermore, the European Commission has just

adopted a proposal for a directive on corporate social responsibility.

In the future, based on the

mechanism that already exists under French law,

these companies should be required to draw up

and implement a vigilance plan containing measures to prevent environmental damage caused by

their activities and those of their subcontractors and suppliers. It will then be through hard law that

companies will be required to take action that will incidentally be beneficial to the implementation

of the Paris Agreement.

On the other hand, through the action of the courts, companies are increasingly ordered both

to commit to reducing their greenhouse gas emissions and to fulfil these commitments. While the

growing risk of a legal sanction – hard enforcement – no longer constitutes an invitation but an

incentive – soft enforcement –, the sanction itself forces the company to take action or to scale up

its efforts and reinforces the initially soft enforcement mechanism set out in the Paris Agreement.

Again, this is evidenced by the climate trials taking place around the world. Initiated in the US,

where they have so far failed to produce results, climate lawsuits against companies are increasing

in other countries. Already, in the wake of the Urgenda case, the Dutch court in The Hague has

condemned Shell for its contribution to global climate change and its consequences at the local

See for instance T. Hickmann (2016), Rethinking Authority in Global Climate Governance, How transnational climate

initiatives relate to the international climate regime, Routledge.

Directive 2014/95/EU of the European Parliament and of the Council of 22 October 2014 amending Directive 2013/34/EU

as regards disclosure of non-financial and diversity information by certain large undertakings and groups Text with EEA relevance,

OJ L 330, 15.11.2014, 1-9.

Proposal for a Directive of the European Parliament and of the Council on corporate sustainability due diligence and

amending Directive (EU) 2019/1937, COM/2022/71 final.

Article L. 225-102-4 of the French Commercial Code.

level, following a liability action brought by environmental organisation Milieudefensie.

Relying,

in addition to hard law instruments, on international soft law instruments and on the various

voluntary acts demonstrating that the company had itself incidentally agreed to ensure that its

activities (and those of the companies within its sphere of influence) reduce their greenhouse gas

emissions, the Court found that Shell had failed to comply with the duty of care imposed on it

pursuant to Article 6:162 of the Dutch Civil Code. Accepting in this case to take into account new

social expectations in order to adapt the content of this duty of care and to play a preventive role,

the judge asked Shell to strengthen its GHG reduction policy. This is quite significant in the context

of our analysis: here, without being a party to the Paris Agreement, the oil company is incidentally

required to participate in the implementation of its objectives. Above all, because this duty of care

is recognised in civil law as well as common law countries, its use in climate litigation is likely to

expand and encourage other carbon majors to strengthen their climate policy.

Indeed, a French court was recently recognised as having jurisdiction to rule on the

proceedings brought by environmental association Notre Affaire À Tous against oil company

Total.

In this case, it is on the basis of the duty of care, but also of the failure to comply with the

“duty of vigilance” (see the aforementioned legal provision) and the system of compensation for

ecological damage (under the Civil Code), that Total could be required to scale up its efforts in the

fight against global warming. Ironically, it is through this “hard” internal control that the

international “soft” enforcement of the Paris Agreement could have a chance to succeed...

Conclusion

Analysis of the enforcement techniques of the Paris Agreement provides two main lessons.

On the one hand, the assessment shows the variety of enforcement techniques - litigation,

transparency, voluntary instruments. It is based on various tools from various legal orders, domestic

and international, producing various, gradual effects, from sanction to incentive to invitation, and

implemented by various actors, some acting through control mechanisms – either because they

carry out such control (the judge for hard enforcement and experts for soft enforcement), or because

they instigate it (plaintiffs in legal proceedings) –, others acting of their own accord and sometimes

outside of any control.

In addition to that, the analysis demonstrates the complementarity of enforcement

techniques. While each technique has its advantages and disadvantages (sanctions allow

compliance to be enforced but are counterproductive in international law; incentives are more

appropriate but may not be effective in practice), it is only when taken together, as part of a global

and complex vision of the law, that these enforcement techniques prove to be complete. Indeed,

the soft law techniques of the Paris Agreement, which are deployed in both the domestic and

international legal orders, play an essentially preventive and incentivising role. If soft law fails or

is insufficient, hard enforcement mechanisms can come into play. In this situation, the benefits of

sanctions resurface.

Despite the way in which the Paris Agreement was designed, and even though its provisions

have no or little direct effect, the Agreement increases pressure on States, including - and perhaps

most importantly - at the domestic level. As scientists continue to warn about the race against time

when it comes to climate change, and given that greenhouse gas emissions are cumulative, any

delay in international action jeopardises the chances to actually hold the temperature increase well

below 2°C and a fortiori below 1.5°C. In the light of the findings of the IPPC-1.5°C-Report,

the

The Hague District Court, 26 May 2021: http://climatecasechart.com/non-us-case/milieudefensie-et-al-v-royal-dutch-shell-

plc/ (last accessed 23 May 2022).

Nanterre District Court confirmed by Versailles Court of Appeal, Notre affaire à tous v. Total:

http://climatecasechart.com/non-us-case/notre-affaire-a-tous-and-others-v-total/ (last accessed 23 May 2022).

IPCC (2018) Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-

industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the

threat of climate change, sustainable development, and efforts to eradicate poverty.

first part of the IPCC’s Sixth Assessment Report (AR6),

and the growing mobilisation of civil

society, it becomes ever more difficult politically speaking for States to stick to national

contributions that, once aggregated, could not lead to a drastic reduction of emissions that would

remain “well below 2°C” and as close as possible to 1.5°C. The Paris Agreement has significantly

contributed to increasing the number of domestic climate trials thanks to the involvement of civil

society. This has given national courts the opportunity to position themselves as important actors

in climate governance. Even if the results are not yet satisfactory, this somewhat renewed form of

international commitment by the States has in turn led to renewed forms of control that - hopefully

- will lead to greater effectiveness.

IPCC (2021) Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment

Report of the Intergovernmental Panel on Climate Change.