Historic Milestone in Ecuador: Constitutional Court Recognizes Individual Animals as Subjects of Rights Protected by the Rights of Nature

Macarena Montes and Kristen Stilt explain how the case of a single woolly monkey in Ecuador turned into a historic milestone for the rights of animals and set a new standard for environmental law.

Grey Woolly Monkey, State of Amazonas, Brasil. Photo credit: Dennis Jarvis via Flickr

On February 4, 2022, the Constitutional Court of Ecuador issued its ruling in the case of Estrellita, a woolly monkey (Lagothrix lagothricha) who had lived with a human family since she was one month old. Estrellita was 18 years old when she was confiscated by the Ecuadorean environmental authority, pursuant to section 147.5 of the Organic Code of the Environment, which prohibits the breeding, possession, and commercialization of wild animals.

The authorities quarantined Estrellita at the San Martín de Baños Zoo, where she died on October 9, 2019. Before learning of her death, Estrellita’s human family filed a writ of habeas corpus on her behalf, requesting her return and that a wildlife license be issued to legally keep her at their home.

The lower court and the Court of Appeals denied the writ of habeas corpus. Despite Estrellita’s death, the Constitutional Court of Ecuador selected the case to develop its jurisprudence on whether animals are subjects of rights protected by the rights of nature in the Ecuadorian Constitution and the scope of writs of habeas corpus regarding the protection of nonhuman animals.

Several individuals and entities filed amici curiae to support Estrellita’s case, including a joint brief by the Brooks McCormick Jr. Animal Law & Policy Program at Harvard Law School (Professor Kristen Stilt and Research Fellow Macarena Montes) and the Nonhuman Rights Project (attorneys Steven Wise and Kevin Schneider). The amicus brief asserted that the rights of nature should protect nonhuman animals, including individual animals such as Estrellita.

It argued that even if the Court was mainly concerned with protection on the species level, species are made up of individual animals, and what happens to an individual animal can have an important impact on the species. 

 Further, it would be arbitrary to draw the line at the number of animals needed to count—2, 3, 4, 10? One should be enough.  

Seven of the nine judges of the Constitutional Court of Ecuador decided to recognize Estrellita as a subject of rights protected by the rights of nature, thereby acknowledging that animal rights constitute a specific dimension of the rights of nature with its own particularities (para 91). The Court accepted the amicus brief’s arguments, challenging the traditional view that only regards ecosystems and species as protected by the rights of nature, not individuals: 

In this sense, this Court warns that animals should not be protected only from an ecosystemic perspective or from a view that focuses on the needs of human beings, but mainly from a perspective that focuses on their individuality and intrinsic value (para 79). 

This becomes relevant because protecting only the species of animals – neglecting the protection of individual animals, which in turn make up the species – endangers a significant number of animals and fuels the idea of the possibility of extinction. Even in the case of animals whose species is not endangered, neglecting or failing to protect individuals also has an impact (para 126). 

The Constitutional Court of Ecuador not only recognized animals as subjects of rights protected by the rights of nature, but also outlined the rights that apply to all or some groups of animals. These include the:

  • Right to exist (para 111).
  • Right not to be hunted, fished, captured, collected, extracted, kept, detained, trafficked, traded, or exchanged (para 112). 
  • Right to the free development of their animal behavior (para112), which includes the right to behave according to their instinct, the innate behaviors of their species, and those learned and transmitted among the members of their population, and the right to freely develop their biological cycles, processes, and interactions (para 113). Animals must be guaranteed sufficient space and social conditions to ensure the possibility of the free development of their animal behavior (para 137).
  • Right to freedom and good living (para 119). Animals have the right to freedom of movement (para 137).
  • Right to food according to the species’ nutritional requirements (para 119). Animals must have access to adequate food and water to maintain their health and strength (para 137).
  • Right to live in harmony (para 119). 
  • Right to health (para 119). Animals must be ensured adequate sanitary conditions to protect their health and physical integrity (para 137). 
  • Right to a habitat (para 119). 
  • Right to demand their rights from the competent authorities (para 121). 
  • Right to physical, mental, and sexual integrity (para 133). 
  • Right to live in an environment that is suitable for each species, with adequate shelter and resting conditions (para 137).
  • Right to life (para 155). Animals must be ensured life in a violence-free environment, as well as an environment free from disproportionate cruelty, fear, and distress (para 137).

Additionally, the Court argued that a wild animal’s rights to life, freedom, and integrity, among others, must be protected regardless of the claims, intentions, or desires of third parties. Thus, if judges determine “that the deprivation or restriction of the freedom of a wild animal is unlawful, they must provide the most suitable alternative for the preservation of the life, freedom, integrity, and other related rights of the victim […]” (para 173). The implication is that the environmental authority in Ecuador failed to meet this requirement by confining Estrellita in the Zoo. It is possible that the conditions in the Zoo contributed to her death. 

Regarding the scope of the writ of habeas corpus, the Constitutional Court considered that, although the writ of habeas corpus was inadmissible in Estrellita’s case due to her death, it can be an appropriate action to request the release of a wild animal depending on the circumstances of the case.

The Court explained that even though it has examined the rights of nature so far in action for protection cases, this does not mean that the action for protection is the only adequate action to protect the rights of nature or any of its elements (such as animals) in Ecuador (para 166). Therefore, the Court stated that judges must examine which action best suits the context and the claims of the case, suggesting that other actions may be adequate to protect the rights of nature, and animals, such as habeas corpus (para 167).

Additionally, the Constitutional Court of Ecuador ordered the Ministry of Environment to develop a protocol that considers and evaluates the circumstances of captive wild animals to guarantee their protection; the amicus brief proposed this very idea. Furthermore, the Court ordered the Ombudsman and Congress to prepare and approve a bill on the rights of animals, based on the rights and principles developed in the ruling.

In this time of catastrophic climate crisis and the sixth mass extinction of species, the Constitutional Court of Ecuador’s latest judgments constitute tremendous legal advances in environmental law and animal rights.

Until Estrellita’s ruling, legal practitioners, scholars, and advocates have centered the protection of nature on ecosystems and species, not individuals.

Moreover, much of the work on the rights of nature did not consider animals as rights holders. However, the Court’s groundbreaking ruling advances the constitutional protection of animals—ranging from the level of species to the individual animal—with their own inherent value and needs.


At the end of each piece, we will from now on ask all blog authors the same question aimed at identifying the exact points where their field of law could contribute to fighting climate change:

If you had the power to change one thing in your legal field to drive climate action – what would it be?

Macarena Montes Franceschini: “I would change the legal status of animals to recognise their enforceable fundamental rights so that the law bans activities that exploit animals, which usually also harm nature.”


Kristen A. Stilt is Professor of Law and Faculty Director of the Animal Law & Policy Program at the Law School. She is also the Director of Harvard Law School’s Program on Law and Society in the Muslim World.
Prior to coming to HLS, Stilt was Harry R. Horrow Professor in International Law at Northwestern Law School and Professor of History at Northwestern University. Stilt’s interest in animal issues escalated while conducting research in Egypt for her PhD in Middle Eastern Studies. While there she became involved with several animal advocacy groups, and still helps fund an Egyptian animal rescue project—in addition to personally rescuing dozens of dogs and cats off the streets of Cairo (three of whom now reside in Cambridge). Egyptian animal issues also became a focus of Professor Stilt’s scholarship and she currently is working on a comparative analysis of the inclusion of an animal welfare provision in the 2014 Egyptian Constitution. Professor Stilt recently discussed the convergence of these issues in a Harvard Law Today feature entitled, The Intersection of Animals, Law, and Religion. She was named a Carnegie Scholar for her work on constitutional Islam, and in 2013 was awarded a John Simon Guggenheim Memorial Foundation Fellowship. She has also received awards from Fulbright and Fulbright-Hays. Stilt received a JD from the University of Texas School of Law, where she was an associate editor of the Texas Law Review and co-editor-in-chief of the Texas Journal of Women in the Law. Stilt holds a PhD in History and Middle Eastern Studies from Harvard University.

Macarena Montes Franceschini is an attorney and doctoral researcher at Universitat Pompeu Fabra’s Law Department. She has been a visiting researcher at Max Planck Institute for Comparative Public Law and International Law in Heidelberg and a Rights Research Fellow at the Brooks McCormick Jr. Animal Law & Policy Program at Harvard Law School, where she will begin a visiting fellowship in 2023. She is also a board member of the UPF-Centre for Animal Ethics, editor of the journal Law, Ethics and Philosophy (LEAP), a member of the Editorial Committee of the Chilean Journal of Animal Law, and the treasurer of the Great Ape Project – Spain. She has written several articles on nonhuman animal personhood, animal rights, and animal law and a book titled Animal Law in Chile.