The Judiciary and Climate: a decade of quiet development since the Paris Agreement 

Text written with Ms Clémence Bourillon, judge, special advisor to the First President and head of the international relations department, with the assistance of Mr James Geist-Mokhefi, jurist at the Cour de cassation’s international relations department

The multifaceted nature, international scope, and intergenerational implications of the global climate crisis demand an institutional response of unprecedented scale. This inherent complexity compels States to adapt continuously their legal frameworks. Traditional legal doctrines often prove insufficient when confronted with systemic challenges irreducible to simplistic solutions. As Mireille Delmas-Marty emphasised, it is imperative to devise of novel pathways to transition from a chaotic pluralism to an ordered pluralism ¹ , capable of addressing the challenges to our collective survival.

While environmental law is fundamentally a universal concern, its highly technical and complex nature appears to demand sustained engagement by legal professionals for full assimilation. This results in litigation that NGO reports have described as “neglected” and “invisible,” accounting for less than 0.5% of all civil litigation and between 0.5% and 1% of cases handled by public prosecutors. ² Despite these modest statistics, the judicial branch plays a significant role in safeguarding the environment and other rights that are balanced in cases involving pollution or the destruction of natural habitats. Without ever encroaching upon the prerogatives of the legislative and executive branches, the judiciary ³ ensures adherence to the rule of law, the Constitution, and the environmental principles it enshrines. Its contribution, while perhaps less extensively publicized than that of administrative or European courts, is no less essential. Its role is exerted less through high-profile decisions and more through the subtle evolution and modernization of established legal concepts. 

The Paris Agreement of 2015 served as a catalyst, prompting judges to take into account environmental considerations more deeply and adopt a forward-looking and systemic approach. Consequently, a considerable body of judicial decisions and practices reflect an approach oriented towards anticipation and adaptation to necessary legal transformations, thereby contributing to the development of a climate law that balances economic interests, individual liberties, and environmental protection. This movement is supported by dialogue with other supreme courts and the European courts.

This article will examine this collective movement and its evolution since the Paris Agreement. It offers an analysis of how the French judicial branch has historically approached environmental and climate issues (1), then explores procedural developments in service of climate justice (2), before addressing the institutional dimension of this mobilization (3).

I – The French Judiciary’s engagement with environmental and climate issues

The judiciary has actively engaged with environmental and climate challenges by adapting existing tools and integrating new legal instruments. This approach demonstrates a driving role, at times preceding the legislator, and leads the judiciary to undertake delicate balancing of interests – occasionally even between different aspects of the ecological imperative itself – not without raising notable legal difficulties, especially regarding causality.

1 – The traditional approach of the judiciary: the evolution of existing legal concepts in light of environmental challenges

The judiciary has adapted established concepts to address environmental challenges, distinguishing between civil and criminal approaches. The judiciary has engaged with environmental and climate issues through pre-existing legal mechanisms, which it has shaped into genuine instruments of environmental justice. 

Firstly, with legal ingenuity in environmental matters, the civil judge has progressively adapted the classic instruments of civil law to environmental concerns, offering a renewed and environmentally focused relevance to traditional concepts in the face of climate matters. This adaptation is notably manifested through two primary avenues: on the one hand, the enforcement against misleading commercial communications, and, on the other hand, the reparation for material nuisances.

Concerning the first avenue, the fight against greenwashing practices illustrates this approach. While the repression of these practices frequently falls under criminal consumer law, ⁴  they can also engage the civil liability of their perpetrators based on the common law of tortious liability under Article 1240 of the Civil Code, provided its criteria are met. These criteria, though well-established, can be particularly difficult to establish in environmental matters. 

Monsanto’s “Roundup” packaging contained unfounded environmental claims that were characterised by criminal case-law as misleading commercial practices. In doing so, the judges defined a standard of conduct whose non-compliance constitutes a civil fault. ⁵

This approach, subsequently consolidated by the legislator, thus allows for the sanctioning of harm suffered by consumers or competitors who are victims of these unfair claims.

Concurrently, and in the realm of material harm to the environment, the civil judge has taken hold of the theory of abnormal neighbourhood nuisances. Originally a creation of case law ⁶ mplicitly linked to the limits of property rights (Article 544 of the Civil Code), it constitutes a pivotal instrument given that it establishes a strict liability regime, ⁷ particularly suited to diffuse pollution or industrial nuisances. The trial judge autonomously assesses the abnormal nature of the nuisance, ⁸ by concretely balancing of the interests at stake, which may include consideration of the social utility of the activity in question, particularly in the context of the energy transition; for instance, the 2018 ruling by the Third Civil Chamber concerning nuisances from a wind farm. ⁹

Indeed, this balancing mechanism finds direct application in the regulation of local environmental conflicts. Litigation concerning abnormal neighbourhood nuisances thus becomes an instrument for the judge to sanction forms of pollution (olfactory, noise) when they exceed a certain threshold, as illustrated by the conviction of a farmer in the Oise region at the end of 2023 for nuisances resulting from intensified agricultural activity. ¹⁰

Indeed, this balancing mechanism finds direct application in the regulation of local environmental conflicts. Litigation concerning abnormal neighbourhood nuisances thus becomes an instrument for the judge to sanction forms of pollution (olfactory, noise) when they exceed a certain threshold, as illustrated by the conviction of a farmer in the Oise region at the end of 2023 for nuisances resulting from intensified agricultural activity. This type of litigation is part of broader tensions surrounding agricultural models whose environmental and climatic impact remains debated. The controversy surrounding the “Ferme des mille vaches” (“Farm of a Thousand Cows”), which combined industrial bovine husbandry with a methanization unit, thereby crystallized the opposition of environmental protection associations against a project perceived as ecologically unsustainable. By arbitrating these conflicts, judges do not merely settle neighbourhood quarrels; they actively participate in defining the local environmental limits of economic activities that may bear climatic implications.

However, in our historical analysis, it seems pertinent to recall that the most significant progress in French civil case-law relating to the environment is the recognition of ecological damage. While the landmark “Erika” ruling was indeed rendered by the Criminal Chamber of the Cour de cassation on 25 September 2012, ¹¹ it was precisely on the basis of the civil claims made by the civil parties that the principle of reparation for direct harm to the environment was enshrined. This ruling constituted a turning point, allowing compensation for objective damages, detached from traditional individual or collective damages. The Court thus fully embraced a non-anthropocentric vision of environmental law, rejecting the notion that environmental law should only be considered and measured through damages inflicted upon humans.

History has made this decision a pillar and a pivotal moment in French environmental law, as this jurisprudential innovation was rapidly followed by the legislator with Law no. 2016-1087 of 8 August 2016 for the reconquest of biodiversity, nature, and landscapes, which introduced a specific regime for the reparation of ecological damage in Articles 1246 to 1252 of the Civil Code. Article 1247 of the Civil Code defines it as “a non-negligible harm to the elements or functions of ecosystems or to the collective benefits derived by humans from the environment.” In its decision concerning the constitutionality of this “non-negligibility” threshold, the Constitutional Council also highlighted the distinction between “pure ecological damage” (harm to nature per se) and “collective damage” (harm to human benefits derived from the environment), confirming the trajectory initiated by the Court of cassation in the “Erika” ruling. ¹²

Since the creation of the civil regime for the reparation of this damage (with priority given to reparation in kind and restoration), ¹³ a body of civil case-law implementing it has progressively developed, illustrating the dialogue between the judiciary and the legislature that leads to the elaboration of a coherent body of new rules and practices that are protective of the environment.

In contrast to the dynamism observed on the civil side, the grasp of ecological issues by criminal law has historically proven more gradual and less “revolutionary.” This gradual evolution is notably explained by the dual constraint of the principles of legality and proportionality of criminal offences and penalties, which requires precise legislative incriminations that have historically often been often delayed or initially incomplete in environmental matters, and by a prosecution policy that long remained below the stakes. This insufficiency is due to several factors highlighted by legal doctrine, as well as by associations and the institution itself. Indeed, the Molins report in 2022 underscored both the inadequacy of ordinary criminal law to the specific problem of environmental litigation and how environmental litigation represented “only a very small part of the activity of criminal courts,” which mechanically limited the opportunities for the repressive judge to build as extensive a body of jurisprudence as its civil counterpart.

Historically, the criminal judge has thus relied on a dispersed corpus of offenses, mainly contained within special statutes and subsequently within the Environmental Code, targeting specific infringements such as water pollution offenses or non-compliant waste management. Faced with the inadequacy of these texts to apprehend the dangerousness of certain behaviours, public prosecutors and judges have at times indirectly mobilized general criminal law offenses, foremost among which is the offense of deliberate endangerment of another person (Article 223-1 of the Criminal Code), although the Cour de cassation has ruled that the protection of the environment per se could not suffice to characterize this offense. ¹⁴

The persistence of this anthropocentric vision of criminal law was a weakness highlighted by legal doctrine, which long called for the creation of an offense of endangerment of the environment, an offense that was slow to materialize. ¹⁵

In this context of often timid public prosecution, the role of environmental protection associations was decisive, acting as veritable catalyst for repressive action. Relying on the provisions of the Criminal Procedure Code and on specific authorizations set out notably in Article L. 142-2 of the Environmental Code, these associations were able, by means of filing a complaint with a civil party claim, to trigger public action and present the voice of the collective interest before the courts. The Criminal Chamber has progressively consolidated the legitimacy of their intervention, characterizing their civil action as an “exceptional right” which must be “strictly confined within the limits set by the Criminal Procedure Code,” yet recognizing their right to reparation for direct and personal moral damage resulting from the infringement upon the collective interests they defend.

The Court has thus repeatedly validated their right to join the proceedings as a civil party, whether for acts of pollution ¹⁶ or harm to wildlife ¹⁷ , consecrating their role as sentinels.

Nevertheless, this traditional body of law and these case-law advances, however significant, have progressively revealed their limitations when confronted with the systematization and exacerbation of environmental damage. It is important to recall that the judicial institution itself drew a severe assessment regarding the ineffectiveness of the traditional framework. The Molins report highlighted the highly technical nature of environmental criminal law, the fragility of the causal link, and sanctions deemed largely ineffective, dominated by “rather low” fines and “rare” imprisonment sentences typically accompanied by a suspended sentence. The report further underscored a trend towards “de facto decriminalization,” where the widespread use of alternatives to prosecution (75% of the criminal response) and the scarcity of correctional judgments (5.4% of environmental offenses) create an impression of impunity, while public opinion and social disapproval steadily increased. This shared sentiment of a failure in the traditional criminal response highlighted the imperative need for a comprehensive overhaul of the repressive arsenal, an observation that justifies the emergence of the new legislative tools that we must now address.

2 – Innovative legal tools: recent legislation addressing the challenges of new litigation 

Confronted with the limitations of traditional legal instruments, the legislator has intervened to equip judges with novel tools, particularly in matters of corporate liability and reinforcement of the repressive arsenal.

This dynamic is notably showcased through the emerging duty of vigilance litigation, stemming from Law No. 2017-399 of 27 March 2017. A pioneering global statute, this text established an unprecedented mechanism for holding multinational corporations accountable. Its objective is to prevent severe infringements upon human rights, personal health and safety, as well as the environment, which could result not only from the parent company’s activities but also from those of its subsidiaries, subcontractors, and established commercial suppliers. To achieve this, the law imposes an obligation on companies exceeding certain workforce thresholds (5,000 employees in France or 10,000 worldwide, including subsidiaries) to develop, publish, and implement a vigilance plan. This plan must include precise and effective measures: a risk mapping, regular assessment procedures for the situation of subsidiaries and partners, adapted risk mitigation actions, an alert mechanism, and a system for monitoring the effectiveness of the measures.

The legal architecture of this framework, which shifts corporate social responsibility (CSR) from a voluntary endeavour to a binding legal obligation, ¹⁸ has opened new avenues for litigation. The sanction regime, revised following the Constitutional Council’s annulment of the initially stipulated civil fine, is underpinned by a two-tiered judicial mechanism, with exclusive jurisdiction vested in the ‘tribunal judiciaire’ of Paris (Tribunal of First Instance of Paris). On one hand, any person demonstrating a legitimate interest to act may, after formal notice, petition the judge to enjoin the company to comply with its obligations. On the other hand, and distinctly, failure to adhere to these obligations engages the civil liability of the company for the reparation of harm that could have been avoided by an adequate and effectively implemented plan.

The litigious implementation of this law has undergone a notable evolution. While a first instance decision in 2023 dismissed an action on procedural grounds ¹⁹ , rulings by the Paris Court of Appeal on 18 June 2024, marked a decisive turning point. ²⁰ By declaring these actions admissible, the Court of Appeal clarified essential procedural points, specifying notably that the summons does not need to target the same vigilance plan if the shortcomings persist, and that an action based on the duty of vigilance can be combined with one relating to ecological damage. This emerging jurisprudence, by removing initial procedural obstacles, now appears to pave the way for a substantive examination of vigilance plans. This movement is further supported by the adoption of the Corporate Sustainability Due Diligence Directive (CSDDD) ²¹ , which includes a climate due diligence obligation, promising an intensification of such litigation.

Beyond the specific regime established by the 2017 law, the very notion of duty of vigilance more broadly permeates general civil case-law. This underlying trend is illustrated by several rulings rendered by the Cour de cassation on 15 November 2023, within the context of the Mediator litigation. In these rulings, the Court held that a manufacturer’s failure in its “duty of vigilance and surveillance,” by maintaining a product in circulation despite knowing its risks, constitutes a distinct fault from a product’s safety defect, thereby engaging its common law tortious liability. ²²

The scope of this solution, although rendered in the realm of public health, warrants emphasis. By thus enshrining the autonomy of an ordinary law fault for breach of a duty of vigilance in the face of a known risk, the Cour de cassation consolidates the contours of a general standard of prudent behavior for companies. Without prejudging the evolution of jurisprudence, this clarification naturally invites legal scholars to consider the scope of such liability for economic actors facing other types of proven risks, particularly environmental and climate-related ones.

From repressive reinforcement to the evidentiary challenge: the dual dynamic of climate litigation 

Given the recurrent observation of the ineffectiveness of the criminal response in environmental matters, the legislator has recently undertaken a substantial reinforcement of the repressive framework. Law No. 2021-1104 of 22 August 2021, known as the “Climate and Resilience” law, which translates a portion of the proposals from the Citizens’ Climate Convention, ²³ constitutes the cornerstone of this new ambition. This ambition unfolds on several fronts, demonstrating a will to apprehend environmental litigation in its entirety, from the characterization of the offense to its judicial treatment.

On a substantive level, the law has recast the nomenclature of environmental offenses by creating a new hierarchy of incriminations. At its base now lies a general offense of environmental pollution, codified in Article L. 231-1 of the Environmental Code, which penalizes severe and lasting harm to ecosystems resulting from the manifestly deliberate violation of a duty of care, with five years of imprisonment and a one million euro fine. In addition, the legislator introduced an offense of endangerment of the environment in Article L. 173-3-1 of the same code. Conceived as an anticipatory offense, this provision allows for the criminalization of dangerous behaviour in itself, upstream of any proven pollution, thereby marking a desire for preventive intervention.

At the apex of this new repressive structure, the text enshrines the much-anticipated offense of ecocide in Article L. 231-3 of the Environmental Code. This is not an autonomous offense, but rather the intentional and, consequently, aggravated qualification of the general offense of pollution and certain waste-related damages, punishable by ten years of imprisonment and a 4.5 million euro fine. While this innovation had been long desired, its enactment has drawn significant doctrinal criticism. The choice of classifying it as a “délit” (serious offense) rather than a “crime”, contrary to the recommendations of the Citizens’ Convention, as well as its inclusion in the Environmental Code rather than the Criminal Code, have been perceived as diminishing its symbolic scope. ²⁴ Furthermore, the complexity of its constituent elements, notably the criterion of “durability” of the harm, precisely set at “at least seven years,” raises questions about the evidentiary difficulties that will ensue and, ultimately, the effectiveness of the text.

This will to toughen environmental criminal standards is not limited to direct harm to ecosystems; it also extends to the probity of ecological discourse. In continuity with Law No. 2020-105 concerning the fight against waste and for the circular economy (known as the “AGEC law”), the Climate and Resilience law has intensified the fight against greenwashing. On one hand, it amended Article L. 121-2 of the Consumer Protection Code so that claims relating to “environmental impact” can explicitly form the basis of a misleading commercial practice. On the other hand, and more importantly, it created an aggravated sanction in Article L. 132-2 of the same code, allowing for the fine to be increased to up to 80% of the advertising expenses incurred, a particularly dissuasive threshold.

Finally, the scope of this substantive reinforcement would remain limited without a structural adaptation of the judicial apparatus. Cognizant of the highly technical nature of the subject matter, the legislator, through the law of 24 December 2020, instituted Regional Environmental Hubs (PREs – Pôles Régionaux de l’Environnement). This specialization aims to centralize and optimize the handling of the most complex environmental cases. This initiative is part of a broader movement to densify the landscape of specialized courts (alongside JULIS ²⁵ , JIRS ²⁶ , PSPE ²⁷ , and PACs ²⁸ ), with the objective of making the criminal response more intelligible and effective, although the structural challenges pointed out by the Molins report on environmental justice remain pertinent.

The evidentiary challenge, a test of the effectiveness of the new repressive framework 

However, this legislative and structural architecture, however ambitious, faces a major challenge that conditions its effectiveness: the evidentiary challenge. Climate and environmental litigation, by its very nature, strains the traditional frameworks of legal proof. ²⁹ In particular, the establishment of the causal link between a generating event (greenhouse gas emissions, polluting discharge, state inaction) and a harm that is, by essence, global, diffuse, and multifactorial, constitutes a structural difficulty. ³⁰ This inherent difficulty compels judges to undertake substantial adaptations of their role and confers a reinforced role on the scientific expert. Without an evolution in evidentiary methods, the toughening of incriminations risks remaining a dead letter. 

The core of this challenge lies in the inadequacy between classical models of liability, designed for direct and localized harms, and the systemic nature of climate change. While civil or criminal liability law has historically been built upon an identifiable chain of causality, climate litigation confronts a dilution of this chain: an actor’s emissions mix in the atmosphere with those of countless others, and their effects manifest on a planetary scale with a significant time lag. This fundamental inadequacy compels the legal system to innovate, at the risk of seeing the right to a healthy environment and climate obligations, including criminal ones, become purely theoretical for lack of effective justiciability.

In this context, the role of scientific expertise has become preponderant. The judge is now largely dependent on the work of authoritative bodies, foremost among which is the Intergovernmental Panel on Climate Change (IPCC). The IPCC reports, by their exhaustive nature, their peer-validation process, and the participation of States in their approval, constitute a factual foundation that is difficult to dispute. Attribution science, which aims to link specific extreme weather events to anthropogenic climate change, is also gaining precision, providing courts with increasingly robust tools. However, the dialogue between science and law remains complex: the judge must translate the probabilities and margins of uncertainty inherent in climate science into a binary legal certainty, necessary for rendering a decision. Legal proof must be established despite the presence of uncertainties.

Facing this complexity, case-law has demonstrated a remarkable capacity for adaptation. In French law, the loosening of evidentiary requirements can materialize through the recourse to presumptions of causality and the method of “serious, precise, and concordant converging evidence.” Furthermore, the precautionary principle, enshrined by European Union law (Article 191 TFEU) and permeating national law, can legitimize judicial action even in the presence of scientific uncertainties, provided plausible indications of a serious risk exist. ³¹

Several emblematic decisions illustrate this evolution. In the case of Urgenda v. Netherlands (2019), the Dutch judiciary dismissed the argument of the State’s negligible contribution to establish causality based on its breach of the duty of vigilance (Articles 2 and 8 ECHR). Following a similar approach, the French administrative courts in L’Affaire du Siècle (2021) and Commune de Grande-Synthe (2021) based causality not on specific pollution, but on the State’s faulty inaction in respecting its own climate commitments. These cases demonstrate a mutation where the generating event becomes the breach of a pre-existing legal obligation, the prejudicial nature of which is supported by scientific consensus.

In sum, faced with the inherent challenges of climate litigation, courts are adapting their evidentiary tools. By mobilizing legal presumptions, converging evidence, and redefining the contours of the causal link, they strive to ensure access to justice and accountability for actors. This pragmatic evolution, which is not exempt from debates on the judge’s role, testifies to the vitality of a legal system that is transforming to respond to the cardinal challenges of contemporary society.

The judicial judge: arbiter of environmental antagonisms

Beyond evidentiary challenges, one of the major complexities of environmental and climate litigation resides in the delicate mission of balancing interests and rights of heterogeneous natures and values. Far from the classic binary opposition between economic development and environmental protection, the judge is now confronted with poly-conflicts where fundamental rights such as the right to a healthy environment, public freedoms like the freedom to conduct a business, subjective rights such as property rights, and diffuse collective interests like biodiversity preservation are intertwined. This weighing of interests is all the more subtle as it sometimes pits the ecological imperative against itself!

Litigation related to the establishment of wind farms is a paradigmatic illustration of this. On one hand, the promotion of renewable energies responds to an “objective of public interest pursued by the development of wind energy,” essential for the energy transition and the fight against climate change. On the other hand, these installations can cause harm to interests both worthy of protection. The judicial judge, when competent, notably to rule on abnormal neighbourhood nuisances or irregularities of an installation ³² , must then undertake a concrete arbitration. They are thus led to confront the objective of decarbonisation with, for instance, the protection of biodiversity and protected species. The case-law of the Cour de cassation bears witness to this difficult reconciliation of “antagonistic environmental objectives,” as when it examines the risk of damage caused by wind turbines to protected species such as the lesser kestrel ³³ or the golden eagle. ³⁴ In these cases, the judge must evaluate whether the measures to avoid and reduce impacts are sufficient to justify the harm caused to wildlife in the name of a superior interest. 

Similarly, the judge must balance the general interest of the wind farm project with the rights of local residents, notably respect for their property rights and their right to a peaceful living environment, often invoked via the theory of abnormal neighbourhood nuisances. The sovereign assessment of the trial judges must then determine whether visual or noise nuisances, despite the public utility of the project, exceed the normal expected inconveniences that everyone must bear. This delicate arbitration perfectly illustrates the new mission incumbent upon the judge: it is no longer merely about choosing between the environment and everything else, but rather about deciding between different, and sometimes competing, facets of the ecological imperative itself, ensuring a conciliation that is not manifestly imbalanced.

However, the existence of these legal tools would remain a dead letter without procedural mechanisms allowing them to be activated, which necessitates analyzing the evolution of the rules governing access to justice.

II – Procedural evolutions in service of judicial climate and environmental Justice

The effective implementation of environmental and climate law also relies on adapted procedural mechanisms, enabling access to justice and the anticipation of damages.

1 – The right of action in environmental matters preserved and extended by the judge

As nature is devoid of recognized legal personality, the French legislator has conferred a preponderant role on associations: that of “sentinels” empowered to bring the collective environmental interest before the courts. This right of action, a condition for the effectiveness of environmental justice, is primarily framed by the provisions of Article L. 142-2 of the Environmental Code. ³⁶ . This vision translates into a rigorous control of the admissibility conditions for their actions. By way of illustration, it excludes the application of the special regime of Article L. 142-2 of the Environmental Code when an association does not possess a valid accreditation, thus requiring the demonstration of personal and direct harm. It is by virtue of this reasoning that it deemed inadmissible the action of an association for endangerment of others, considering that a legal entity cannot, by its nature, suffer a risk of harm to its physical integrity. ³⁷ This requirement of rigor extends to purely formal aspects, as shown by the rejection of a civil party claim that had not been preceded by a complaint ³⁸ personally filed by the association. ³⁹

However, this formal severity is counterbalanced by a particularly innovative substantive case law. The Criminal Chamber has indeed enshrined a very broad conception of the moral harm suffered by associations. It is now established that the mere transgression of environmental regulations, even without proven physical harm to ecosystems, suffices to cause indemnifiable moral harm to accredited associations, provided that this violation impinges upon the collective objective they defend (Crim. 29 June 2021, no. 20-82.245). The Court subsequently specified that this moral harm is perfectly autonomous and can be cumulated with the reparation of pure ecological harm (Crim. 25 January 2022, no. 21-84.366), thus offering a dual path for compensation and considerably strengthening the scope of associative action.

Consolidation by the Civil Chamber: the autonomization of associative action

This strengthening movement finds a powerful echo within the Third civil chamber, which has contributed to autonomizing associative action from the criminal sphere. In a landmark ruling on 30 November 2022, concerning the mortality of protected falcons caused by wind turbines, the Court made two major clarifications. On one hand, it asserts that the admissibility of an accredited association’s civil action is not conditional on the finding of an offense by the criminal judge; the mere existence of “facts likely to constitute a criminal offense” suffices. On the other hand, it held that the civil judge, by personally ascertaining the violation of the law to characterize a civil fault, does not infringe upon the separation of powers but fully exercises their office. ⁴⁰ This dynamic extends to urban planning litigation. Pursuing its reasoning, the Court admitted that the disregard of urban planning rules, even procedural ones, may justify an action for demolition, provided however that the applicant association demonstrates a personal harm resulting directly from failure. ⁴¹

Ultimately, through convergent interpretations, albeit distinct in their approach, the Civil and Criminal chambers of the Cour de cassation solidify the status of associations as a pillar of environmental judicial defense. They confer upon it the means to act effectively, making it the de facto representative of a legally voiceless nature.

The impetus from Strasbourg: supranational legitimation of the action brought by an association in environmental and climate matters

This internal dynamic, through which the French judicial judge consolidates the role of environmental associations, is today considerably reinforced and legitimized by a decisive impetus from the European Court of Human Rights (ECHR). The Grand chamber ruling in Verein KlimaSeniorinnen Schweiz and others v. Switzerland, rendered on 9 April 2024, indeed constitutes a foundational decision that redefines the contours of climate litigation in Europe and, by extension, in France.

The Strasbourg Court was confronted with a major obstacle: the difficulty for individual applicants to demonstrate personal harm of sufficient intensity to satisfy the traditional criteria for victim status regarding climate change. To overcome this pitfall without, however, opening the door to an actio popularis (which it prohibits), the Court made a fundamental distinction. It recognized that the diffuse and transgenerational nature of climate damage justified adjusting access to its court for groups.

Thus, the Court forged a specific status allowing an association to act, provided it meets three conditions: being legally constituted in the defendant State, having as its statutory purpose the defense of the fundamental rights of persons affected by climate change, and being considered “truly representative” of the interests it defends. This praetorian law construction is of paramount importance because it confers upon associations a form of “victim by qualified representativity” status. This status allows them to overcome the practical impossibility for individuals to directly claim violations of their rights. Firmly anchoring its reasoning in the right to a fair trial (Article 6 § 1 of the Convention), the Court ruled that refusing such an association a substantive examination of its grievances, supported by science, would infringe upon the very substance of its right of access to a court.

For the French legal system, the implications of this decision are potentially significant. Although domestic law already possesses a specific action regime for associations, the KlimaSeniorinnen ruling provides a supranational standard of interpretation that could influence the judge’s role. It reinforces the legitimacy of actions linking climate issues to the infringement of fundamental rights, including those directed against private actors. Consequently, trial judges, as well as the Cour de cassation, will be encouraged to interpret the admissibility conditions of French law in light of these European standards, in order to guarantee the principle of effectiveness of the Convention. This aims to ensure effective access to Justice in the face of a systemic challenge, thus confirming the trajectory of judicial openness that national case-law had already outlined.

2 – New procedural tools serving environmental justice

Procedural transformation: from reparation to anticipation

Beyond substantive adjustments, the climate challenge necessitates a procedural transformation that directs the judge’s role towards anticipation ⁴² Confronted with the long temporality of damage and scientific uncertainty, the judge adopts a proactive stance. This evolution corresponds to what Blanche Lormeteau and Marta Torre-Schaub describe as an “anticipatory model,” embodied in litigation that aims to neutralize “climate-killing” (‘climaticide’) ⁴³ projects before their effects become irreversible ⁴⁴ . Procedure thus becomes the instrument of an actively assumed responsibility towards future generations. The judge’s role is no longer merely to assess damage ex post, but to extend to its prevention, placing them “upstream” of decisions with potentially irreversible consequences.

To equip the judge in this mission, the legislator and case-law have fashioned a range of specific tools, enabling more agile judicial intervention better adapted to the different stages of litigation.

Levers for anticipation and proof

One of the principal instruments of this preventive approach is the environmental interim relief proceeding (référé pénal environnemental). Although long-standing, this mechanism allows the liberty and detention judge, at the prosecutor’s request, to urgently order any useful measure to halt pollution, including by suspending operations. Its effectiveness has been reinforced by the Cour de cassation, which ruled that its implementation was not conditional on the prior characterization of an offense, thus facilitating rapid judicial intervention in front of a proven risk ⁴⁵ .

In addition to emergency intervention, environmental justice requires instruments capable of overcoming the inherent evidentiary difficulty. To this end, in futurum expertise (pre-trial evidence gathering), provided for in Article 145 of the Civil Procedure Code, proves to be a strategic tool. Allowing for an investigatory measure to be ordered “if there is a legitimate reason to preserve or establish, before any trial, proof of facts upon which the resolution of a dispute might depend,” it offers potential plaintiffs the means to build a solid case. The Cour de cassation, which ensures that the judge has assessed the utility of the measure for a potential dispute that is not manifestly bound to fail ⁴⁶ , has entrusted the appreciation of the “legitimate reason” to the sovereign assessment of the trial judges ⁴⁷ . In environmental matters, where evidence is technical and prone to deterioration, this tool constitutes a procedural translation of the precautionary principle, allowing for the preservation of elements before the causal link becomes impossible to establish. 

Towards a negotiated justice and a collective reparation?

Concurrently with the reinforcement of preparatory tools for trial, the legislator has explored alternative avenues aimed at a more pragmatic resolution of harms. The judicial public interest agreement (CJIPE “Convention judiciaire d’intérêt public environnementale”), introduced in 2020 by Article 41-1-3 of the Criminal Procedure Code, falls within this logic. As an alternative to prosecution for legal entities, it allows the prosecutor to suggest an agreement whereby a company, without admitting guilt, undertakes to pay a fine, implement a compliance program, and, crucially, repair ecological harm. This agreement, validated by a judge, thus articulates sanction, prevention, and reparation, ensuring concrete corrective measures that a simple pecuniary conviction would not guarantee.

Finally, this overview is complemented by the potential of class action litigation to address the issue of mass damages. While the CJIPE targets ecological harm, the class action, introduced in 2016, offers a pathway for collective reparation of individual harms stemming from the same breach. Although its use in environmental matters remains limited, its potential for addressing diffuse harms and improving access to justice is now clearly identified. Its effective deployment would constitute a decisive step in adapting judicial treatment to environmental challenges.

III – Judiciary in motion: institutional adaptations and jurisdictional dialogue

Confronted with the specific nature and increasing technicality of environmental and climate litigation, the French judiciary, and first and foremost the Cour de cassation, has undertaken profound changes. These illustrate, on one hand, its resolute engagement in an extended jurisdictional and institutional dialogue, essential for building a coherent and shared legal response, and on the other hand, through internal structural and intellectual adaptations aimed at strengthening its capacity to handle these complex disputes.

1 – Jurisdictional dialogue, a source of shared normative construction 

The action of the Cour de cassation in environmental matters cannot be apprehended in a vacuum; it is situated at the heart of a dense network of national and transnational exchanges that nourish and guide its case-law. This dialogue dynamic is particularly structuring in its relations with European courts, where it has evolved from a simple reception of case-law towards genuine cooperation, organized by procedural mechanisms designed for this purpose. The reference for a preliminary ruling to the Court of Justice of the European Union remains, in this regard, an essential tool for ensuring the uniform interpretation and effectiveness of Union law. Added to this is the advisory opinion procedure provided for by Protocol No. 16 to the European Convention on Human Rights, which allows the Cour de cassation to consult the Strasbourg Court in advance on matters of principle. France was, moreover, the first country to utilize this mechanism ⁴⁸ . These instruments are particularly valuable for addressing new and complex issues hand in hand, and this could thus be the case in the area of climate rights.

Beyond European institutional frameworks, the Cour de cassation actively participates in direct comparative dialogue with its foreign counterparts. This dialogue, which can be formal or informal, unfolds within bilateral or multilateral settings, such as the Network of Presidents of the Supreme Judicial Courts of the European Union or the Franco-British-Irish Judicial Cooperation Committee. These forums are not limited to institutional questions; they allow for the discussion of substantive legal issues, as evidenced by the exchanges on climate justice during the Committee meeting in Edinburgh in June 2024. In-depth discussions on emblematic cases like Heathrow Airport (UK Supreme Court) or Grande-Synthe (French Council of State), as well as on the ECHR’s KlimaSeniorinnen judgment, highlighted the shared challenges faced by high courts, particularly concerning the temporality of judicial action and the effectiveness of their decisions.

This external cooperation is now complemented by a more innovative form of dialogue, expressed at the very heart of the Court’s decisions. The recent stylistic revolution in the drafting of its rulings, and notably the advent of “enhanced reasoning” for the most important cases, opens the way for a new practice ⁴⁹ . This drafting technique allows for the integration into the judge’s reasoning, not as a source of law but as a reference or comparative light, of solutions developed by foreign courts. In a field as novel and intrinsically transnational as climate litigation, it is easy to anticipate that the Cour de cassation could mobilize this faculty to enrich its own climate reflection by drawing inspiration from the case-law of other States.

These pragmatic exchanges, whether external or internal to the reasoning, nourish the Court’s reflection and demonstrate a growing Europeanization of climate litigation. This trend is so pervasive that it has even led some to advocate for an enlargement of the powers of bodies like the European Public Prosecutor’s Office or Eurojust, or even for the creation of a specialized international court ⁵⁰

At the national level, the coherence of the legal edifice rests on indispensable internal cooperation with the Council of State and the Constitutional Council. The strengthening of the constitutional basis for environmental protection owes much to the mechanism of the priority question of constitutionality (QPC), which enabled the recognition of the normative scope of the 2004 Environment Charter. The so-called “Michel Z.” case strikingly illustrates this joint role of the Supreme Courts. Seized of a dispute relating to the exemption from liability for neighbourhood disturbances under the theory of “pre-occupation”, the Cour de cassation exercised its filter function. Deeming the question novel and serious with regard to Articles 1 to 4 of the Charter, it transmitted it to the Constitutional Council. Through its subsequent decision ⁵¹ , the Council made a major advance. By agreeing to exercise its review with regard to the rights and obligations stemming from the Charter, it consecrated for the first time the directly invocable nature of everyone’s right to live in a balanced environment and everyone’s duty to participate in its preservation. This decision thus transformed these principles into enforceable reference standards, making the Charter a living legal instrument serving the litigant.

This dialogical construction carries on and enriches itself. The recent recognition by the Constitutional Council of the constitutional value of “common goods” and “the interests of future generations” ⁵² is likely to permeate the case-law of the judiciary, which will be called upon to integrate this prospective dimension into its review. Institutional convergence is also visible in the participation of the magistrates of the Court in international reflection committees, alongside members of the Constitutional Council. Finally, this dialogue extends to academic doctrine, whose contributions, integrated via conference cycles and the monitoring by the Documentation, Studies and Report Service (SDER), are essential to enable the Court to base its decisions on a robust interdisciplinary analysis, commensurate with the complexity of climate challenges.

2 – Internal adaptations of the judicial system in response to the increasing complexity of disputes

To better apprehend the systemic challenges of new litigation, the Cour de cassation has first strengthened its internal capacities for analysis and foresight. Structures like the SDER and its Observatory of Judicial Disputes (OLJ) have become essential instruments of this transformation. The OLJ, the Court’s structure aimed at linking with trial courts to identify emerging litigation, has asserted itself as an active monitoring unit on matters such as the duty of vigilance and corporate social responsibility (CSR). This proactive approach materialized on 7 May 2025, with the creation of a thematic college dedicated to CSR. This aims to anticipate future waves of litigation, particularly those related to the CSDDD, and to feed the debate on this major public interest subject by bringing together all of the Observatory’s partners.

Beyond this foresight function, indispensable for improving the quality and responsiveness of Justice, the SDER also provides daily support to the judicial work of magistrates, particularly when confronted with new questions in their cases. By disseminating thematic studies, it guides, without commanding, the judges’ reflection and thus promotes early harmonization of legal approaches.

This structural adaptation is accompanied by an essential openness for forging a common legal culture. Since 2022, the Cour de cassation has organized annual conference cycles dedicated to environmental transformations, placed under the direction of specialized academics. The thematic progression of these colloquia — from the foundations of civil liability (2022), to environmental commitments and “greenwashing” (2023), then to the judge’s role in the face of long timeframes (2024) — reveals a structured and committed institutional approach. In parallel, the National School for the Judiciary (ENM ‘Ecole Nationale de la Magistrature’) has significantly strengthened its programs, notably via the Advanced Environmental Justice Cycle (CAJE), which involves leading figures such as climatologist Valérie Masson-Delmotte, as well as academics and lawyers involved in research projects or litigation relating to climate disputes. These combined efforts aim to raise the level of expertise at all levels of the judiciary, ultimately enabling the Cour de cassation to produce high-quality climate case-law, rendered by magistrates who master these new issues.

Beyond these institutional adaptations and this normative dialogue, the evolution of environmental case-law is also driven by a non-negligible generational factor. Indeed, the new generation of magistrates progressively joining the courts approaches these issues with a sensitivity and familiarity intrinsically different from those of their elders. Trained at university and then at the National School for the Judiciary at a time when the Environmental Code was fully established, when the 2004 Charter for the Environment was enshrined in the Constitution, and when the Paris Agreement had redefined global climate ambitions, these judges and prosecutors have integrated these texts as fundamental components of positive law. For them, environmental protection does not constitute a legal revolution or a normative conquest; it represents a pre-existing legal landscape, a foundation of their professional culture. This ingrained understanding could thus foster a more direct and unrestrained application of environmental law, considering its principles not as programmatic objectives, but as legal standards of immediate application, at the heart of their role. The future of environmental justice is assured.

Conclusion

Ten years after the Paris Agreement, the French judiciary has asserted itself as a key actor in the implementation of environmental law. Its contribution has consisted of giving practical effect to legal texts through a pragmatic adaptation of existing tools and the consecration of new concepts. The recognition of ecological harm, initiated by case-law before being enshrined in law, is the most striking example. By evolving civil liability from a logic of simple reparation towards a preventive function, the judicial judge has contributed to consolidating the edifice of environmental protection.

However, this role, though significant, is still under construction and remains incomplete. Entire segments of judicial action are not yet deemed satisfactory, whether from the perspective of the litigant, legal scholars, or legal professionals. The most severe observation concerns the effectiveness of environmental criminal law.

Beyond the criminal sphere, the full potential of innovative procedural tools, such as class actions or duty of vigilance litigation, still needs to be fully deployed to become truly effective. Similarly, the delicate articulation between scientific expertise and judicial decision remains a constant challenge. It is therefore by pursuing an in-depth dialogue with other national and European courts, and by tackling these ongoing projects, that the judiciary will be able to fully accomplish its mission: to ensure, through a rigorous and coherent application of the law, effective protection of the environment and the rights that underpin it.

The first decade since the Paris Agreement has been one of adaptation. The next will determine if this subtle evolution is sufficient given the scale of the crisis, or if it is merely the prelude to a deeper judicial revolution that the judiciary has, until now, avoided.

1. Delmas-Marty M., Les forces imaginantes du droit. Vol. II: Le pluralisme ordonné, Seuil 2006
2. Report of the working group on environmental criminal law, chaired by Mr. François Molins, Prosecutor-General at the Cour de cassation, 2022
3. The judicial branch in France comprises two sub-branches: the Ordre administratif that handles public law matters and the Ordre judiciaire, competent for private law (including criminal law). Their respective Supreme Courts are the Conseil d’Etat and the Cour de cassation
4. Article L121-2 of the Consumer Protection Code defines greenwashing as “allégations, indications ou présentations fausses ou de nature à induire en erreur [notamment le consommateur et les investisseurs sur] les caractéristiques essentielles du bien ou du service, à savoir : ses qualités substantielles, sa composition (…), ses propriétés et les résultats attendus de son utilisation, notamment son impact environnemental [et] la portée des engagements de l’annonceur, notamment en matière environnementale”.
5. Crim., 6 October 2009, n°08-87.75.
6. Landmark ruling of the Civil Chamber, dated 27 November 1844.
7. Civ. 3rd, 4 February 1971, n° 69-12.739
8. Civ. 2^nd, 19 November 1986, n° 85-15.098.
9. Civ. 3rd, 13 September 2018, n° 16-23.694.
10.  Civ 3rd, 7 December 2023, n° 22-22.137.
11. Crim., 25 September 2012, n° 10-82.938.
12.  Constitutional Council, 5 February 2021, QPC n° 2020-881.
13. Article 1249 of the Civil Code states that: “la réparation du préjudice écologique s’effectue par priorité en nature. En cas d’impossibilité de droit ou de fait […] le juge condamne le responsable à verser des dommages et intérêts, affectés à la réparation de l’environnement […]”. The emphasis is therefore placed on the concrete restoration of the altered environment, before any payment of monetary compensation
14. Crim., 5 April 2011, n° 09-83.277, Stocamine.
15. See also in this regard : Faure, Michaël G., “Vers un nouveau modèle de protection de l’environnement par le droit penal”, Revue Européenne de Droit de l’Environnement 9.1 (2005), Neyret, Laurent, “Pour la reconnaissance du crime d’écocide”, Revue juridique de l’environnement 39.HS01 (2014), or Hurel, Benoist, “Droit pénal de l’environnement: une situation largement perfectible”, Délibérée 8.3 (2019), among many others.
16. Crim., 5 October 2010, n° 10-80.278.
17. Crim., 25 June 2019, n° 18-83.420
18. Moreau, Marie-Ange, “L’originalité de la loi française du 27 mars 2017 relative au devoir de vigilance dans les chaînes d’approvisionnement mondiales”, Droit Social 10 (2017)
19. Total Energies case, T.J. Paris, 28 February 2023
20. Paris Court of Appeal, 5^th Division-12^th Chamber, 18 June 2024, RG n° 23/14348
21. First Article, 1c : … l’obligation pour les entreprises d’adopter et de mettre en œuvre un plan de transition pour l’atténuation du changement climatique qui vise à garantir, en déployant tous les efforts possibles, la compatibilité du modèle économique et de la stratégie économique de l’entreprise avec la transition vers une économie durable et avec la limitation du réchauffement climatique à 1,5°C conformément à l’accord de Paris.
22. Civ. 1st, 15 November. 2023, nos 22-21.174, 22-21-178, 22-21.179, 22-21.180 B.
23. Ollier C. and Benichou M., “Retours sur les mesures adoptées, modifiées et avortées de la Convention Citoyenne pour le Climat”, Crises climatiques, crises sociales, résilience et ruptures. 2023.
24. Radisson L., “Loi climat : de nouveaux délits qui risquent de ne pas dissuader les pollueurs”, ActuEnvironnement, 2021 ; “Loi Climat : la création d’un nouveau délit controversé d’‘ecocide’ votée par les députés », Le Monde, 19 March 2021.
25. Juridictions du littoral spécialisées, specialized coastal jurisdictions.
26.  Juridictions interrégionales spécialisées, specialized interregional jurisdictions.
27. Pôles de santé publique et de l’environnement, Public and environmental health hubs.
28. Pôles accidents collectifs, Mass accidents units.
29. Canali L., “La preuve par l’expertise dans le contentieux français des changements climatiques”, Revue juridique de l’environnement 47.3 (2022).
30. See Krakau M., Causation in National and International Climate Change Litigation, Springer (2025) and Pfrommer, Tobias, and al. “Establishing causation in climate litigation: admissibility and reliability.” Climatic Change 152.1 (2019).

31. Article 191 of the TFEU: 

    Union policy on the environment shall contribute to pursuit of the following objectives:

    • preserving, protecting and improving the quality of the environment,
    • protecting human health,
    • prudent and rational utilisation of natural resources,
    • promoting measures at international level to deal with regional or worldwide environmental problems, and in particular combating climate change.

32. See in this regard Civ 1^st, 14 February 2018, n°17-14.703
33. Civ. 3st, 30 November 2022, n° 21-16.404.
34. Civ. 3rd, 11 January 2023, n° 21-19.778

36. Article 142-2 of the Environmental Code: Les associations agréées mentionnées à l’article L. 141-2 peuvent exercer les droits reconnus à la partie civile en ce qui concerne les faits portant un préjudice direct ou indirect aux intérêts collectifs qu’elles ont pour objet de défendre et constituant une infraction aux dispositions législatives relatives à la protection de la nature et de l’environnement, à l’amélioration du cadre de vie, à la protection de l’eau, de l’air, des sols, des sites et paysages, à l’urbanisme, à la pêche maritime ou ayant pour objet la lutte contre les pollutions et les nuisances, la sûreté nucléaire et la radioprotection, les pratiques commerciales et les publicités

    trompeuses ou de nature à induire en erreur quand ces pratiques et publicités comportent des indications environnementales ainsi qu’aux textes pris pour leur application.Ce droit est également reconnu, sous les mêmes conditions, aux associations régulièrement déclarées depuis au moins cinq ans à la date des faits et qui se proposent, par leurs statuts, la sauvegarde de tout ou partie des intérêts visés à l’article L. 211-1, en ce qui concerne les faits constituant une infraction aux dispositions relatives à l’eau, ou des intérêts visés à l’article L. 511-1, en ce qui concerne les faits constituant une infraction aux dispositions relatives aux installations classées.

    [/notes] However, it is the case-law of the Cour de cassation, both civil and criminal, which, through a dialectic between procedural rigor and substantive audacity, has progressively consolidated the position of associations as indispensable actors in litigation.

    The Criminal Chamber’s dual approach: formal rigor and substantive boldness

    
    As already mentioned, the Criminal Chamber characterizes the action of associations as an “exceptional right” that must be “strictly confined within the limits set by the Criminal Procedure Code” ³⁵ Crim. 25 September 2007, n°05-88.324, Bull. crim n°220, D. 2007. 2671; ibid 2008. 109, chron. D. Caron and S. Ménotti; AJ penal 2008. 83, obs. C. Saas; RSC 2008 108, obs. A. Giudicelli

37. Crim. 8 September 2020, n° 19-85.004.
38. Plainte simple.
39. Crim. 8 September 2020, n° 19-84.995
40. Civ. 3rd, 30 November 2022, n° 21-16.404.
41.  Civ. 3rd, 11 January. 2023, n° 21-19.778
42. Fort, François-Xavier. “L’office du juge administratif sous influence climatique.” Revue juridique de l’environnement 47.4 (2022): 689-701.
43. Neologism : that contributes negatively to climate change.
44. Lormeteau, B. and Torre-Schaub, M., Du nouveau dans le contentieux climatique – Des réponses temporelles et plurielles à l’urgence climatique. Revue juridique de l’environnement, spécial (HS1) (2021), 257-274.
45. Crim. 28 January 2020, n°19-80.091
46. Civ 1st., 25 October. 2023, n° 21-24.930.
47. Civ 2^nd, 10 December 2020, n° 19-22.619.
48. Request for an advisory opinion of the Cour de cassation dated 16 October 2018
49. The Guide to Enhanced Reasoning (26 September 2023) is available on the public website of the Cour de cassation.
50. International legal scholarship has been analyzing the project’s feasibility and advocating for it since the 1970s, with a significant acceleration following the emergence of climate litigation in the 2000s
51. n° 2011-116 QPC of 8 April 2011.
52. Ruling of 27 October on the Cigéo project.