When Does a Right to Life Arise?

The question of when a legal right to life first arises in the course of a human being’s development is pertinent to a variety of contexts, including protection of prenatal life from injury by persons other than the gestational mother, what to do with frozen embryos when the couple who created them divorces, and how to treat children born with severe disabilities, as well as the more familiar context of state regulation, restriction, or prohibition of abortion. This chapter first summarizes social and biological science findings relevant to this question, then details development of legal rules and constitutional doctrine pertaining to abortion regulation before contrasting that with protections for prenatal life in other contexts. It concludes that the most coherent answer to the question when a right to life arises is that the right to life is coextensive with the biological life of the human being, and that a legal right to remain alive arises when a human being comes into existence and continues until it ceases to be a human being—that is, when its life has ended. This might provide justification for greater restrictions on abortion, but that could depend on additional considerations.