Commune de Grande-Synthe v. France

Vulnerable Coastal Municipality Successfully Challenges the French Government’s Climate Inaction

A coastal municipality in France particularly vulnerable to the effects of climate change successfully challenged the federal government’s inaction on climate change. The Conseil d’Etat ordered the federal government to take all necessary actions to reduce greenhouse gas emissions, on the basis of its domestic and international climate obligations. Since the judgment was issued, the Conseil d’Etat has ordered the federal government to pay two penalty payments in light of its failure to take adequate steps to implement the decision.


On November 19, 2020, the Conseil d’Etat (the French Supreme Administrative Court) issued a historic judgment, finding that the French government had failed to take sufficient action to mitigate climate change and ordering it to take additional measures to address its failures.

The case was filed by the municipality of Grande-Synthe and its mayor. Grande Synthe is in northern France and borders the English Channel. It is located below sea-level and, as a result, is facing some of the worst and most serious climate change impacts in France. There is a high risk of flooding, and the municipality anticipates that it will have significant issues with its water management system.

The case began with letters sent by Grande-Synthe to the French authorities, asking for them to increase their efforts in the fight against climate change. On November 19, 2018, Grande-Synthe asked the President of France, the Prime Minister, the Minister of State, and the Minister of Ecological Transition and Solidarity to:

  1. Take measures to reduce greenhouse gas emissions produced within France to respect the country’s climate change obligations.
  2. Take all legislative or regulatory initiatives to “make climate priority mandatory” and to prohibit any measure likely to increase greenhouse gas emissions.
  3. Implement immediate measures to adapt to the effects of climate change.

The relevant authorities never responded to Grande-Synthe’s letter.

And so, on January 23, 2019, Grande Synthe sued the French Government, arguing that the French government’s failure to take adequate action to reduce greenhouse gas emissions breached its obligations under domestic and international law. It argued that the federal government failed to respect the carbon budgets it set under its National Low Carbon Strategy and that the government’s climate policies were not consistent with its climate obligations.

First Decision – November 19, 2020

The first hurdle was having the court find that the municipality’s claims were admissible. The French government challenged the plaintiffs’ claims, saying the plaintiffs lacked legal standing and that the pleadings were defective and lacked merit.

The Court held that the municipality’s petition was admissible. Its reasoning was partially based on the fact that the municipality was “particularly exposed to the effects of climate change,” being a coastal city under sea level. The Court relied heavily on IPCC reports and climate science produced by the National Observatory on the Effects of Global Warming (ONERC in French) on the likely effects of climate change. It used this evidence to draw support for the plaintiffs’ claim that the municipality of Grande-Synthe would be badly affected by climate change and to justify the need for stronger climate action.

The Conseil d’Etat noted that France had largely fallen afoul of its carbon budget over 2015-2018. Further, the way it calculated its carbon targets meant that the bulk of emission reduction efforts were shifted to after 2023 – requiring France to follow a very ambitious emissions reduction trajectory after this date. As a result, the Conseil d’Etat instructed the government to demonstrate, within three months, that it was taking adequate steps towards meeting its 2030 climate goals. In effect, this meant that France needed to provide evidence that it was not “implicitly refusing” to take “any useful measure[s]” to reduce greenhouse gas emissions.

The Conseil d’Etat signaled that the case should be determined by reference to French and European law. But it still considered the Paris Agreement and UNFCCC to be important. It considered both agreements to be relevant to the interpretation of national law. For instance, it accepted that by signing up to the UNFCCC and the Paris Agreement, France had “committed to fight against harmful effects of climate change.”

Although the Conseil d’Etat made several findings in the plaintiffs’ favor, it refrained from definitively deciding the case. It found that it did not have enough information to decide whether France had taken sufficient actions to reduce emissions. Instead, it ordered the federal government to provide additional evidence and submissions.

The Court’s Final Decision – July 1, 2021

The Court issued its final decision on July 1, 2021. It found that the French government had not taken the additional measures necessary to “bend the curve of greenhouse gas emissions” and that its refusal to take appropriate regulatory actions was incompatible with its emissions targets.

It ordered the government to “take all the measures necessary” by the end of March 2022 to reduce emissions, in order to meet a 40 percent reduction by 2030. It noted that this would require the government to go further than what it was already doing, noting that current climate regulations were insufficient to meet its targets.

Penalty Payments

Under French law, courts may impose penalties on the state if its efforts to comply with the specific performance obligations under a judgment are deemed insufficient.

To this end, the Conseil d’Etat ruled in July 2020 that if the French government did not take sufficient measures to reduce greenhouse gas emissions within the six months following its decision, the French state would be ordered to pay a penalty of 10 million euros every six months if the government failed to improve its climate action as required.

The Conseil d’Etat has ordered the government to pay at least two sets of 10 million euro damages since it issued its decision (on August 4, 2021 and October 17, 2022). The Court’s evaluation of the federal government’s implementation of the measures necessary to comply with the judicial decision remains ongoing.

€10 million

The amount of the penalty imposed on the French government for failing to meet its emission reduction targets


Population of Grande-Synthe

40% by 2030

France’s emissions reduction target, developed pursuant to the Paris Agreement


Emphasizing the urgency of taking climate action now, given the compounding and permanent effects of climate change as time progresses.

The Conseil d’Etat recognized there was an “urgent need to act” on climate change.

The importance of taking urgent action in order to protect more vulnerable communities from the worst effects of climate change was a key driver behind this case. This is reflected in the Conseil d’Etat’s decisions. For instance, it was concerned about the way the government was setting its carbon targets, which deferred “the bulk of the effort beyond 2020.” This required levels of emission reductions in future years “that had never been reached before.” Some commentators have suggested that the Court indirectly recognized the existence of a climate emergency, in the sense that states have an obligation to act quickly.

Tying countries’ climate and human rights obligations to international climate and environmental law, including, for example, the temperature target established by the Paris Agreement.

Although the Court did not decide the case on the basis of France’s obligations under the Paris Agreement, its international climate obligations were an important part of the Conseil d’Etat’s reasoning. It noted that the Paris Agreement and UNFCCC should be taken into consideration when interpreting national law and held that they represented a commitment by the federal government to fight the “harmful effects of climate change,” including by developing policies aimed at reducing emissions.

“[The Paris Agreement and UNFCC] must be taken into account in the interpretation of the provisions of national law.” [Decision]

Shifting the presumption of proving the adequacy of countries’ climate actions to the respondent countries.

In its interim decision of November 19, 2020, the Conseil D’Etat required the federal government to prove that it was taking adequate actions to meet its 2030 climate goals. The burden of proof fell to the federal government. It is worth noting that in its final decision of July 1, 2021, the Court was not satisfied with the federal government’s proposed actions and ordered the government to do more – and take “all measures necessary.”


Regions particularly vulnerable to climate impacts can challenge their government’s decisions or inaction on climate change. This case is an important example of local municipalities serving as plaintiffs in a challenge to federal government climate policy.

“Due to its immediate proximity to the coast and the physical characteristics of its land, the municipality of Grande-Snythe faces increased risks of floods, severe drought episodes, the reduction and degradation of freshwater resources, and of significant damage to property and built-up areas…. [This] is likely to justify the need to act without delay.” [Decision] (Translation from French)

The Court relied on established climate evidence, such as IPCC reports, in support of its decision.

The Court did not shy away from criticizing the government’s approach to its climate goals and took a relatively hands-on approach to monitoring the government’s progress. The procedure concerning the evaluation of the implementation of the government’s measures is currently ongoing, and the Court has imposed significant damages on the French government for its failure to comply.


Commune de Grande-Synthe v. France was one of the first cases in France where the federal government’s inaction on climate change was successfully challenged. It was the first of a string of cases in France challenging the French government and was followed by cases such as Notre Affaire à Tous and Affaire du Siècle.


Paris temperature goal
The Paris temperature goal refers to the goal that the Paris Agreement establishes to “hold the increase in global average temperature to well below 2˚C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5˚C above pre-industrial levels, recognizing that this would significantly reduce the risks and impacts of climate change” (Article 2(a)).

Other Case Studies:

O’Donnell v. Commonwealth
In October 2021, the Federal Court of Australia declined to dismiss a novel class action lawsuit brought...
Institute of Amazonian Studies (IEA) v. Brazil
In the face of devastating deforestation in the Brazilian Amazon, an NGO seeks the recognition of a fundamental...
Leghari v. Pakistan
Climate litigation often focuses on the Global North. But one of the earliest, most prominent rights-based...