To understand which legal rights the Nonhuman Rights Project is demanding for nonhuman animals, we need to understand what legal rights are. During World War I, a young Yale law professor, Wesley Hohfeld, tried to understand what judges mean when they talk about legal rights. He concluded that legal rights were advantages conferred by legal rules upon one legal person against another. One person always has a legal advantage (that’s the right), while another legal person always has the corresponding legal disadvantage. It always takes two. Like “Love and Marriage,” you can’t have one without the other.
Not everyone agrees Hohfeld got rights right. And his system can get complicated. But most common law judges, when they start dissecting legal rights, eventually find their way back to Hohfeld. Remember: only a legal person has the capacity to have a legal right. That’s why legal personhood is the bull’s-eye for the Nonhuman Rights Project.
Hohfeld came up with four correlating pairs of advantages and disadvantages, which include four kinds of legal rights. A “liberty” allows a person to do as she pleases, but she has no right to have her liberty respected. It’s merely a permission without a protection and it correlates with the “no-right”. A person with a “no-right” has no claim on another person to do, or not to do, anything.
A “claim” demands some respect. It places a correlating “duty” upon another person to act, or not act, in some way towards the claimant. You agree to sell me your house: I agree to pay you for it. I have a claim on you for your house; you have a claim on me for the money (you still with me?).
A “power” affects the legal rights of any other person “liable” to be affected; the power to sue is probably the most important power.
Finally, an “immunity” legally “disables” one person from interfering with another. Claims say what one should not do; immunities what one cannot legally do. You cannot enslave me, as human slavery is prohibited; humans are immune from enslavement. Such immunities as freedom from slavery and torture are the most basic kind of human legal rights. And it’s these legal rights that the Nonhuman Rights project argues that at least some nonhuman animals are most strongly entitled.