With the retirement of Justice Anthony Kennedy, legal commentators on both left and right speculate that the next Supreme Court Justice may be the deciding vote to overturn Roe v. Wade. After all, Justice Kennedy coauthored the decision to retain Roe in Planned Parenthood v. Casey (1992) and sharpened the undue burden standard in Whole Woman’s Health v. Hellerstedt (2016). His abortion jurisprudence perpetuated a nationalized “right to abortion” with no basis in the original meaning of the Constitution. Self-described originalists of the sort included on President Trump’s list of potential Supreme Court nominees are unlikely to continue that legacy.

What would happen if Roe were overturned? Most assume that each state would have unfettered authority to make its own abortion policy. That was, after all, the position of the late Justice Antonin Scalia. He argued that each state should exercise “democratic choice” through the “political process” to determine whether abortion would be legal. Justice Scalia disagreed with “anti-abortion people who think that the constitution requires a state to prohibit abortion.” Instead, he argued, “when the Constitution says that persons are entitled to equal protection of the laws … it clearly means walking-around persons.”

Does the Constitution really only protect “walking-around persons”? What if overturning Roe meant not simply punting the issue to the states, but rather acknowledging a constitutionally guaranteed right to life for unborn children? What if the Fourteenth Amendment, as originally understood, protected every human being—born or unborn? In a recent article for the Harvard Journal of Law & Public Policy, I present an originalist case for extending the constitutional guarantees of due process and equal protection to the unborn.

My argument is simple: The Fourteenth Amendment’s use of the term “person” includes every living member of the human species who is within the Constitution’s jurisdictional reach. Each member of the human species begins his or her individual existence at the moment of fertilization. Therefore, the Fourteenth Amendment protects every member of the human species from the moment of fertilization. The minor premise—that the preborn are biological members of the human species—is an incontrovertible scientific fact. Thus, all that must be demonstrated is that the original public meaning of the term “person” at the time the Fourteenth Amendment was adopted included all members of the human species.

At the time of the Fourteenth Amendment’s adoption, dictionaries of both common and legal usage treated the term “person” interchangeably with “human being” or “man.” The 1864 edition of Noah Webster’s Dictionary of the English Language, for example, defined “person” as relating “especially [to] a living human being; a man, woman, or child.” “Human” is in turn defined to include all those belonging to “the race of man.” In legal usage, every human being was considered to be a “natural person.” Alexander Burrill’s New Law Dictionary and Glossary, published in 1851, defined “person” as “A human being, considered as the subject of rights, as distinguished from a thing.” Much earlier, William Blackstone’s influential Commentaries had declared that “life is … a right inherent by nature in every individual.” For Blackstone, if human life existed, legal personhood existed also. There was no distinction between biological human life and legal personhood.

Centuries of English common law tradition consistently treated abortion as the wrongful killing of a human being. From her founding, the United States adopted this tradition and prohibited abortion as soon as human life could be detected. In the early years of the American republic, unborn life was detected at “quickening,” which is the first perceived fetal movement. The “quickening” standard was a useful legal brightline rule for proving the elements of the crime of abortion. When embryologists discovered in the 1830s that each human individual begins its life cycle at fertilization, states quickly discarded the obsolete quickening standard and adopted the medically accurate fertilization standard in its place. The Pennsylvania Supreme Court’s ruling in 1850 that “the moment the womb is instinct with embryo life, and gestation has begun, the crime may be perpetrated” is indicative of the national mood regarding abortion in that era.

When the Fourteenth Amendment was adopted in 1868, the states widely recognized unborn children as persons. Twenty-three states and six territories referred to the fetus as a “child” in their laws prohibiting abortion. Twenty-eight classified abortion as an “offense against the person,” or a functionally equivalent classification. These statutes were enacted in recognition of unborn human beings’ full and equal membership in the human family. In Ohio, the same legislature that ratified the Fourteenth Amendment in January 1867 passed legislation criminalizing abortion at all stages just three months later. Several senators who voted for the Fourteenth Amendment’s ratification sat on the committee that reviewed the anti-abortion bill. They acknowledged in their report that “physicians have now arrived at the unanimous opinion that the foetus in utero is alive from the very moment of conception,” and declared on that basis that abortion “at any stage of existence” is “child-murder.” In light of the historical evidence, there can be little doubt that the original public meaning of the term “person” in 1868 included unborn children.

The framers of the Amendment themselves expected that it would guarantee due process and equal protection for every human being within the jurisdictional reach of the Constitution. Representative John Bingham, the Amendment’s primary drafter, believed it would prevent states from refusing “any of the rights which pertain … to common humanity.” Representative Thaddeus Stevens called the Amendment “a superstructure of perfect equality of every human being before the law; of impartial protection to everyone in whose breast God had placed an immortal soul.” During congressional debates, Representative James Brown asked rhetorically: “Does the term ‘person’ carry with it anything further than a simple allusion to the existence of the individual?

How shocked the framers of the Fourteenth Amendment would be to discover that their Amendment had been twisted a century later to justify the slaughter of millions of defenseless human beings. Although their subjective intentions do not govern the meaning of the ratified text, they shed considerable light. It is worth pondering whether this radically inclusive amendment, designed to guarantee protections for every human being, could be reasonably interpreted to exclude a subset of individuals who were considered to be human beings at the time it was written. The Fourteenth Amendment was meant to be a new birth of freedom for all human beings.

In his Roe v. Wade majority opinion, Justice Harry Blackmun acknowledged that if “personhood is established,” the case for a constitutional right to abortion “collapses, for the fetus’ right to life would then be guaranteed specifically by the [Fourteenth] Amendment.” Under an originalist interpretation of the Constitution, the legal edifice supporting Roe collapses and a robust jurisprudence of constitutional rights for the unborn arises in its place. The Equal Protection Clause, as originally understood, prevents states from refusing to prosecute the intentional killing of the unborn while continuing to prosecute the killings of other classes of persons.

Skeptics might call this proposed pro-life jurisprudence fanciful or dismiss it as a fringe legal theory. Surely, they say, there aren’t five votes for recognizing constitutional personhood for the unborn. But Justices who wish to ascertain and apply the original meaning of the Constitution must examine the evidence and follow where it leads. If Roe is to be overturned, let us hope that Justice Kennedy’s successor is not a faint-hearted originalist.

Josh Craddock is a recent graduate of Harvard Law School.