The European Court of Human Rights (ECHR) has declared inadmissible the lawsuit filed on behalf of the Mar Menor against Spain, a decision especially relevant because it forced Strasbourg to confront an unprecedented situation: an ecosystem recognized as a legal person by a European state going to the court responsible for protecting the rights enshrined in the European Convention on Human Rights. The Court has ultimately rejected the claim, but the ruling contains an important nuance: it does not invalidate or question the legal personality of the Mar Menor recognized by Spanish legislation.
The lawsuit argued that the right of access to a court had been violated after the Provincial Court of Murcia prevented environmental organizations from intervening as a private prosecution on behalf of the lagoon in proceedings for possible environmental crimes. Strasbourg concludes that the interpretation made by the Spanish courts "was not manifestly unreasonable or arbitrary" and considers that, in those specific circumstances, the Mar Menor could not present itself as a victim of a violation of the Convention.
Where the case comes from
The origin lies in an investigation opened by the Investigating Court number 4 of Cartagena for possible environmental crimes linked to pollution from agricultural activities. The Alianza Mar Menor Association (AMARME) tried to represent the lagoon and act as a private prosecution, relying on Law 19/2022, which turned the Mar Menor and its basin into a subject of rights.
However, the Provincial Court of Murcia revoked that possibility. Among its arguments was that the body legally responsible for representing the Mar Menor was not yet constituted and that environmental organizations could not simply assume that representation in the criminal proceedings. After exhausting other avenues, AMARME took the matter to Strasbourg arguing that access to Justice for the lagoon had been unjustifiably restricted.
What Strasbourg recognizes
The first issue that must be clarified is that the legal personality of the Mar Menor is not granted now by Strasbourg. The lagoon already has it in Spain since the approval of Law 19/2022. Its article 1 expressly declares the Mar Menor and its basin subjects of rights and article 6 establishes that any natural or legal person can act judicially in defense of the ecosystem, presenting the action "in the name of the Mar Menor ecosystem as the true interested party."
The Constitutional Court subsequently supported that formula. In its ruling 142/2024, it declared the law constitutional and described the norm as the first in the euromediterranean scope that attributes legal personality to a natural entity. The Constitutional Court considered that the legislator had created "a new type of legal person, a natural reality" with powers aimed at defending its existence and recovery.
The novelty of the European ruling lies in that the ECHR has entered to examine a claim made by an ecosystem with that national legal personality, instead of simply dismissing it because the claimant is not a human person or a company. Lawyers and organizations defending the Mar Menor interpret this fact as a recognition of its "ecological legal personality" in the European procedural plane and qualify it as a historic precedent.
This nuance is important: Strasbourg takes into consideration the legal personality that Spain has granted to the lagoon, but does not create a new European right of nature nor establishes that all ecosystems can now go to the ECHR.
What it does not recognize: the Mar Menor was not a "victim" in this procedure
The unfavorable part of the decision lies in the concept of victim. For a claim to prosper before the ECHR, it is not enough for the claimant to have legal personality: they must also demonstrate that they have been a victim of one of the rights protected by the Convention.
Strasbourg considers that this did not occur in this specific case. The lagoon did not initiate the original criminal procedure by itself and its subsequent appearance as a private prosecution was annulled by the Provincial Court according to an interpretation of the procedural rules that the ECHR does not consider arbitrary. Therefore, the Court concludes that the Mar Menor cannot invoke here the victim status required by the Convention and unanimously declares the claim inadmissible.
The resolution, therefore, does not condemn Spain, does not grant compensation to the Mar Menor, and does not determine that the right to a fair trial has been violated.
It also does not decide who polluted the Mar Menor
Another important element is what Strasbourg was not judging. The ECHR did not have to decide whether an ecological crime occurred, who polluted the lagoon, or who should pay for its recovery. The issue analyzed was procedural: whether preventing that appearance under the conditions in which it occurred violated the right of access to Justice.
Therefore, the inadmissibility does not imply a favorable or unfavorable ruling on the investigations for agricultural pollution nor a general assessment of the ecological state of the Mar Menor. Those issues correspond to the proceedings opened before the Spanish courts.
AMARME also does not obtain its own legitimacy
The association AMARME also attempted for Strasbourg to recognize its own legitimacy to raise the claim, but the court also does not accept that argument. The organization had invoked, among other elements, the doctrine developed by the ECHR in climate litigation that has exceptionally allowed certain associations to act in defense of affected individuals.
Strasbourg considers that this exception cannot be automatically transferred to this procedure because the matter of the Mar Menor was not a climate change litigation. The well-known climate jurisprudence of the court does not, therefore, turn any environmental organization into a legitimized victim to approach the ECHR for any environmental damage.
The representation problem that existed in 2024 has changed
The legal context is also different from that existing when the Provincial Court adopted the decision that originated the litigation. One of the problems then was that the bodies intended to officially represent the Mar Menor had not yet finished being constituted.
The Government approved in February 2025 Royal Decree 90/2025 to develop that structure. The regulation created the effective functioning of the Tutorship of the Mar Menor, which encompasses the Committee of Representatives, the Monitoring Commission, and the Scientific Committee, and expressly attributed to that institution the legal representation of the lagoon before authorities, public bodies, companies, and courts.
This does not mean that a future lawsuit before Strasbourg will be admitted, but rather that the procedural problem that weighed on the 2024 procedure is not reproduced exactly in the same terms.
Can the Mar Menor return to Strasbourg?
The decision does not equate to stating that an ecosystem can never be a victim of a violation of the European Convention. The defenders of the lagoon emphasize precisely that the ECtHR has studied the claim taking into account its specific circumstances and has not established a general prohibition that definitively closes that possibility.
However, it would be excessive to interpret the resolution as if Strasbourg had already recognized human rights specific to the Mar Menor. It has not done so. The European Convention is still fundamentally designed to protect the rights of individuals and certain legal entities, and the question of how far it can extend to a natural entity remains legally open.
The conclusion is, therefore, twofold. Strasbourg dismisses the lawsuit and validates the procedural actions of the Spanish courts in that case, but does not question the legal existence of the Mar Menor created by Spain. The lagoon remains a subject of rights under Spanish law; what it has not achieved, at least in this first attempt, is for the European Court of Human Rights to consider it a victim of a violation of the Convention.