Animals have changed the way I think about rights.

Before studying animal care, I never really considered the idea that animals could hold legal rights. Yet in recent years, animal welfare advocates have challenged this assumption by bringing court cases on behalf of captive animals, arguing for their right to liberty.

To do so, they primarily use the legal approach; habeas corpus, a Latin term meaning "you shall have the body." This is a centuries-old legal remedy, traditionally used to protect people from unlawful imprisonment, and is now being explored in cases involving animals.

The main question, though, is how exactly can habeas corpus be applied to animals?

From what I’ve learned, the process itself is actually highly complex because for an animal to be granted habeas corpus, it must be legally recognised as a ‘legal person’ with basic rights like liberty before other legal actions can be taken. However, and here's the catch, animals are classified as property. As a result, they cannot automatically claim rights in the same way humans can.

This made me wonder: ‘Is there a list of animals that can be granted habeas corpus?’. Most cases brought so far have involved cognitively complex species, such as great apes and elephants, since their advanced cognition and autonomy have supported legal arguments presented in court. However, as of today, there isn’t an exact list of animals eligible for habeas corpus. Ultimately, the granting of habeas corpus depends on the country’s legal framework and the court's interpretation of the law.

This is what makes these cases particularly challenging. Rather than simply advocating for improved welfare or living conditions, they question a long-standing legal principle by asking whether animals should continue to be classified as property or instead be recognised as individuals capable of holding certain legal rights.

In terms of real life cases involving animals and habeas corpus, there are two examples that particularly interested me. This is because they demonstrate how cases like these can lead to different outcomes.

The first example is Happy, the Asian elephant from the Bronx Zoo. Happy lived most of her life alone, raising concerns about her welfare. In 2018, the Nonhuman Rights Project filed a habeas corpus case arguing that she should be recognised as a legal person with the right to freedom. The court eventually denied her habeas corpus, so she remained at the Bronx Zoo until her passing in May of 2026. Although it wasn't the first animal habeas corpus case, it became one of the most influential as the case itself sparked worldwide discussion about animal rights and autonomy.

Happy the Asian Elephant. Source

The second example is Cecilia, a chimpanzee kept in captivity in Mendoza, Argentina. Cecilia was kept in harsh solitary confinement in a zoo until an organisation named Association of Officials and Lawyers for Animal Rights (AFADA) filed a habeas corpus petition on her behalf. The court granted it, recognising her as a "non-human person" with fundamental legal rights, including the right to liberty. As a result, Cecilia was transferred from a zoo in Mendoza to a sanctuary in Brazil. This is a groundbreaking case as not only was Cecilia granted habeas corpus, she was the first chimpanzee to have ever been granted it.

Cecilia the Chimpanzee. Source

Cecilia in the Zoo v.s. in the Sanctuary. Source

Learning about cases like Happy’s and Cecilia's completely changed the way I think about animal rights. It showed me that questions surrounding animal welfare are not only scientific but also ethical and legal, challenging how society defines and classifies rights, personhood and freedom regarding animals.