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When Is an Animal a Legal Person?

Defining rights for non-humans beyond bestowing them with “personhood” can only become more important as we learn more about animal cognition.
(Photo: William Warby/Flickr)

(Photo: William Warby/Flickr)

This is not a trick question: Is a chimpanzee a person? If you asked the average human being that question, you'd probably get a quick "no." In the eyes of the law, however, that’s still an open question.

Last week, a New York Supreme Court judge submitted a court order that appeared to give two research chimpanzees the writ of habeas corpus—the right to challenge unlawful detainment. Previously, habeas corpus has been extended only to legal persons, so experts speculated that the order implicitly acknowledged the chimps, named Hercules and Leo, as legal persons. But the very next day, the judge amended the order. In the document, she scribbled over the words “writ of habeas corpus,” apparently to sidestep any speculation about the chimps’ personhood status. The next court date is set for May 27; then, Stony Brook University, where Hercules and Leo are being held, will have to present a legal argument for why they are detaining the chimps.

Hercules and Leo’s case is one of several lawsuits filed by the Nonhuman Rights Project, an animal rights non-profit. In the eyes of the law, animals are still considered things. They can be given protections—for instance, the Animal Welfare Act lays out guidelines for the ethical treatment of research animals, while the Humane Slaughter Act sets standards for farming animals—but without personhood, they are still subject to be kept as human property. This is what the NhRP seeks to change; they believe that seeking legal personhood for animals will make the task of arguing for the chimps’ freedom from detainment an easier process.

Given that corporations, counties, and cities can be legal persons, it doesn’t seem like a huge stretch to confer personhood to animals too. This practice of declaring clearly-not-people as legal persons is called a “legal fiction.” Because we’ve created such a complex labyrinth of laws, it’s easier to fit in new concepts (like non-human entities having rights) by incorporating them into the old legal architecture. This leads to all sorts of weird exceptions; for instance, while corporations and cities can be legal persons, they are not actual people and they are incapable of emotions, and therefore aren’t able to act with malice or having privacy.


The law is a reflection of a general trend among humans: anthropocentrism, which basically says that people conceive of everything relative to the very distinct human experience. Whether the NhRP strategically planned to start with lawsuits on behalf of primates, it was a smart strategy; it takes advantage of our intuitive sense that primates are somehow like us—and therefore might also deserve rights.

In any case, what qualifies a being as deserving of rights? The NhRP has vowed to fight for personhood for other “intelligent” animals, like dolphins, whales, and elephants. But exactly what constitutes intelligence is hotly debated in the animal cognition world, and, ultimately, our definition is heavily biased toward our own species’ traits.. We think of ourselves as the smartest creatures around, so we look for human-like traits in animals. Some markers researchers have identified include self-awareness, planning and problem solving, learning from peers, and communication skills. Given these human-centric criteria, it’s unsurprising that humans are the only animals known to reliably meet all of them. Still, many other species have been shown to possess a subset of these indicators. While the NhRP recognizes animals like the primates, dolphins, whales, and elephants as intelligent, there are many other animals that we regularly overlook: Bees perform complex dance moves to show their peers where food is; crows wait for cars to crush nuts for them to eat; and lizards are capable of problem solving.

In any case, it doesn’t seem like the cognitive abilities of animals have any bearing on their legal protection. There are plenty of smart cold-blooded animals—birds, reptiles, fish, even insects—but only warm-blooded animals are covered by the AWA, which defines standards for research animals or animals for commercial sale. Standards for farm animals are generally lower—they are designed to ensure animals will not suffer “unnecessary cruelty”—though farm animals are not necessarily any less intelligent than animals covered under the AWA. Chickens are adept at problem-solving, especially when food is involved, and and appear to empathize with peers in distress. Octopuses solve complicated problems, and can even form opinions about individual humans. Pigs appear capable of deception. Fish learn from watching other fish.


It seems inevitable that as we learn more, the way we think about and treat animals will change. But our current legal system just isn't set up to incorporate the nuances of our growing knowledge about animal cognition. In Hercules and Leo’s case, the NhRP is pursuing personhood status for the chimpanzees really just for one right: freedom from detainment. Still, an argument for personhood presents the simplest strategy to obtaining that freedom.

This cumbersome process of recognizing animals as “persons” is essentially a Band-Aid for a bigger problem: We don’t have any other legal concept in place that can be used to define rights for non-human beings. Developmental psychologist Jean Piaget’s theories about infant learning come to mind. Piaget postulated that when babies come across new ideas, they must decide either to assimilate the idea into an existing concept they have, or, if the idea doesn’t fit well into any existing concepts they have, to create a new concept to accommodate the idea.

This line of thinking can be applied to the chimpanzee court case. The legal system has chosen to assimilate animals, corporations, and counties into its already-existing legal definition of “person,” rather than accommodating the idea with a new legal category all its own. Though we’re making do with these legal fictions for now, defining rights for non-humans beyond bestowing them with “personhood” can only become more important as we learn more about animal cognition or if we encounter new classes of things we want to give rights to, like machines and artificial intelligence.

Regardless of whether Hercules and Leo are recognized as legal persons, their case has started a dialogue about animal cognition that society will be forced to re-visit as we reconcile our knowledge about animals’ intelligence with our treatment of them. If there’s one thing that’s clear about animal cognition, it’s this: We humans are certainly the only animals that create laws to govern other animals.