A law for the jungle

We should extend the right to liberty and equality to non-human animals, argues Steven Wise.

The shock and novelty of the idea that basic legal rights for at least some non-human animals should be acknowledged has worn off. As "animal rights" arguments develop, they are becoming more nuanced, both as to which animals should have rights and what rights they should have.

Recognising the large number and stunning diversity of animal species, proponents are not arguing that all should be given legal rights or be treated the same. Why should a chimpanzee, a dolphin, a dog and a cockroach be given the same rights? Basic rights protect basic interests. The basic interests of a gorilla may be quite distinct from those of a parrot or a horse. And because an animal might be entitled to legal rights does not necessarily mean she should gain rights beyond the most fundamental. A chimpanzee, for example, should have the right to bodily integrity but not the right to vote.

Arguments for many non-human animals to be given rights do not require new legal approaches. The strongest argument is that they should be entitled to rights for some of the same reasons that humans are: liberty and equality. A being is entitled to a right to liberty because of how she is put together. She is entitled to a right to equality because she resembles, in some relevant way, another with that right.

Liberty is the more complex argument. Judges have long considered autonomy as sufficient for basic rights. One kind of autonomy, what I call "practical autonomy", exists when a being can desire, act intentionally to achieve her desires and have some sense that the life she is living is hers.

Any being who is self-conscious has at least some elements of theory of mind (she knows what others see or know), understands symbols, uses a language-like communication system and perhaps deceives, pretends, imitates and solves complex problems clearly has practical autonomy and should be entitled to at least some basic rights. These will tend to be those animals that are closest to humans on the evolutionary scale, but not necessarily so.

On a four-category scale of autonomy values that I have devised, such beings clearly fall into category one. These include normal adult chimpanzees, bonobos, gorillas, orang-utans and Atlantic bottle-nosed dolphins. Any category-one animal should, at the very least, have the same legal right to bodily integrity as does a human three-year-old child. She could no more be used in biomedical research or as a food source than they could.

Category-four animals are not entitled to any legal rights. That does not mean we can treat them as we wish, especially if they can feel pain; it only means that they may not have rights. Category-three animals are those animals - probably the great majority - about whom we do not know enough to be able to make a rational decision about the category into which they should be placed.

Category-two animals include those whose mental abilities are either well known and fall below the minimum and those for whom evidence of self-consciousness is lacking, as is every element of theory of mind. They may, however, possess a simpler consciousness, be able mentally to represent and act insightfully, perhaps use a simple communication system, and have a primitive sense of self. Or their mental abilities may be largely unknown, but those that we do know about may include some complex ones.

The animals closest to category one should be given legal rights as a reasonable precaution against our committing the grave wrong of violating the bodily integrity of an autonomous being. Category-two animals entitled to basic legal rights include African grey parrots and African elephants. Like category-one animals, they should be treated no worse than three-year-old children.

Equality is the simpler argument for the basic rights of any non-human animal. If likes should be treated alike, it is difficult to argue that an anencephalic human baby, insentient, unable to feel pain, who possesses the right to bodily integrity, should be treated so vastly better than many category-two animals. So an animal lacking practical autonomy might still be entitled to legal rights as a matter of equality.

Steven M. Wise has taught animal rights law at Harvard Law School and is author of Unlocking the Cage , published this week by Perseus Press, £9.99.

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