In what might still be the most famous moral-philosophical defense of abortion, Judith Jarvis Thomson admitted that “we shall probably have to agree that the fetus has already become a human person well before birth.” “By the tenth week,” Thomson observed, the fetus “already has a face, arms and legs, fingers, and toes; it has internal organs, and brain activity is detectable.” Though she denied that “the fetus is a person from the moment of conception,” she granted that proposition for the sake of arguing for a broad right to abortion.

“Opponents of abortion commonly spend most of their time establishing that the fetus is a person, and hardly any time explaining the step from there to the impermissibility of abortion,” she observed, but “it is by no means enough to show that the fetus is a person, and to remind us that all persons have a right to life,” for “we need to be shown also that killing the fetus violates its right to life, i.e., that abortion is unjust killing” (emphasis added).

Thomson tactically conceded fetal personhood, hoping to show that the right to abortion does not turn on the question of a fetal right to life. To put it differently, Thomson understood that the central question of the abortion debate concerned the extent to which abortion could be justified if it is the killing of one person by another. If it could be justified at all, the justification would have to appeal to principles that can be applied consistently across the board.

Hence her argument cited general norms of justification, widespread intuitions, and tutored reactions to life-threatening scenarios. Her examples involved grown-up physically independent people: the parable of the Good Samaritan, burglars climbing in one’s window, Henry Fonda applying a life-saving touch to the forehead of the author. For Thomson, abortion presented a unique type of fact pattern, but to illumine the requirements of justice, she thought, one had to consider general principles governing the ethically appropriate use of deadly force against anyone.

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My aim is not to engage Thomson’s conclusions about the scope of justified abortion but rather to show that her question is the question today in American law. The legal system since Roe v. Wade and through Planned Parenthood v. Casey has neglected to ask the question about the consequences of fetal personhood, fearing—rightly—the damage the answer could do to the right to abortion. But this insulation of abortion rights leaves the courts unable to rule consistently in a variety of cases where the fetal right to life has become lodged in law. Ultimately the debate must return to Thomson’s question.

The Abortion Postulate in Our Constitutional Law

Neither in Roe nor in Casey nor in any other case has the Supreme Court taken up the task of arguing that the victim of an abortion is not a homicide victim; the Roe Court infamously declined to “resolve the difficult question of when life begins.” Nowhere has the Supreme Court provided grounds for denying that people come to be at fertilization, notwithstanding the Court’s recognition that the constitutionality of abortion rights decisively rides on this question.

Casey affirmed what it called the “central holding” of Roe v. Wade: women must have the “ultimate” authority to decide about continuing a pregnancy. Casey’s affirmation rested not upon ratification of Roe’s reasoning but upon social expectations that came to be after 1973. For two decades, the subscribers to the Casey joint opinion wrote, people “have organized intimate relationships and made choices” while relying on access to abortion in case contraception should fail. Lower courts since Casey have leaned largely on the strength, not of legal or ethical (or scientific or medical) reasoning, but on the quarter-century-old Supreme Court precedent. When considering the proposal that mothers must respect the right to life of the unborn, they have done little more than repeat the depersonalizing term “potential life.”

Some courts have even reasoned backwards from abortion to the nonexistence of fetal rights: since abortion must be just, the unborn cannot possess any rights that would prevent a decent society from countenancing lawful abortion. Chief Judge Richard Posner of the Seventh Circuit encapsulated this inversion well when he wrote, in 1998, that the conclusion that the fetus is not a person “follows inevitably from the decision to grant women the right to abort.” Posner’s bald inference shows that the permissibility of abortion has acquired the character of a postulate of our constitutional law. In this way, the legal culture has turned Thomson upside-down. While she argued that personhood and the right to life were insufficient for ruling out all abortions, many people today think a right to abortion tells against the personhood of the unborn. But the existence of a regime permitting abortion establishes nothing of the sort about the true status and rights of the child in utero.

The non-negotiability of the right-to-abortion axiom is especially evident in June’s Supreme Court case, Whole Woman’s Health v. Hellerstedt. So long as Roe is the law of the land, the pro-life movement has had to limit the number of abortions by way of creative legislation; for instance, regulations that require informing women about fetal development and about alternatives to abortion. Waiting periods and mandatory ultrasounds aim to provide women a chance to reconsider the humanity of their children. And in states like Texas, pro-lifers managed to pass legislation requiring abortionists to have hospital admitting privileges, and requiring abortion clinics to meet minimum standards of care that they will not meet, effectively forcing those clinics to close.

It was over against these latter Texas regulations that the Supreme Court most recently expanded the scope of abortion rights in Whole Woman’s Health. Whole Woman’s Health raised the bar of judicial review for state regulations of abortion grounded in concerns for maternal health. The case even appears to hold that reasonable maternal health laws are unconstitutional, where they substantially impede some women’s access to abortion. This holding is evidence that such maternal health regulations have crested, especially where they are enacted with a view not only to women’s health but to reducing the overall incidence of abortion.

Whole Woman’s Health did not touch the constitutionality of abortion regulations for the sake of informed consent, and there is surely space for further refinement of such approaches. But these too have, for the most part, plateaued as anti-abortion measures; future refinements will not yield dramatic decreases in abortion rates. As long as the right to abortion continues to function as an axiom, as it does in Whole Woman’s Health, it will seem natural that measures restricting abortion must meet a very high bar. To tackle the nearly one million abortions that take place in the United States each year, pro-lifers must press the question that the courts have ignored. The future of the anti-abortion movement lies in restrictions founded on the fetus’s right to life.

The Truth Cannot Be Suppressed

How, though, can Thomson’s question have any effect on legal practice, when over forty years of precedent have ignored it?

Conscientious legislators have recently enacted two types of abortion restrictions protecting the unborn as rights-bearers. One type involves prohibitions that recognize (as did Thomson) that the fetus is a person “well before birth,” and even before “viability.” Examples include bans after the point of “fetal pain” (at about twenty weeks) or after “fetal heartbeat” (at about eight weeks). Such laws represent attempts to align abortion regulation more closely with the scope of morally justified killing.

The second tranche of recent pro-life legislation would ban entirely abortions sought for particularly unworthy reasons, such as the sex or race of the unborn child. These enactments establish a fetal-personhood beachhead (so to speak) by linking the unborn to the wider community of persons protected against unjust discrimination.

Such prohibitions also reconnect the discussion with Thomson’s approach of affirming “the permissibility of abortion in some cases” while rejecting in every case “the right to secure the death of the child.” Just as you could “unplug” a renowned violinist whom the Society of Music Lovers attached to your kidneys, Thomson thought an unwillingly pregnant woman could eject a fetal squatter. Her question was about the grounds of knowingly causing the death of an unborn person by and through an act undertaken for the purpose of terminating a pregnancy.

This was essentially the question raised by an Indiana statute recently enjoined by a federal judge. Indiana defended its prohibition on race- and sex-selective abortions by noting, inter alia, that women affected by the ban obviously did not object to being pregnant or to carrying a child to term. The only desire that these laws disrupted was the woman’s wish to have a little girl rather than a little boy (or vice versa). Women seeking a sex-selective abortion are obviously not aborting for the sake of ending a pregnancy; they are seizing the opportunity pregnancy affords them in a post-Roe world to terminate a child whose sex is undesirable. Such laws recognize a fetal right to life and seek to distinguish spurious from non-spurious reasons for its defeat. In this way, they raise Thomson’s question about the extent to which the fetal right to life must be protected.

Being Consistent About Feticide

The most compelling reason why Thomson’s question is our question is also why the prevailing regime of stipulation-and-avoidance cannot much longer evade evidence and reason. What Thomson granted for the sake of argument has become an established fact: the unborn are recognized as persons with a right not to be killed in 38 American states, as well as in federal law. These statutes—commonly described as “feticide prohibitions”—accord the unborn the same right to life as others, except when they are targeted in legal abortion.

Some feticide defendants have challenged their convictions on constitutional grounds, chiefly equal protection of the laws. If the norms of justified killing never bar a mother from killing her child, they ask, then why are do they always prevent a father from acting in the same way, for the same reasons? Ambient norms of justification should govern everybody, they point out, just as they should protect everybody.

And the feticide defendants have a point: as far as abortion precedent is concerned, fathers and mothers are equally justified in killing their fetal children. Roe listed seven types of “detriment” as reasons for permitting abortion. One of them—the “stigma” of unwed motherhood—has largely disappeared, now that fully 40 percent of children are born to unwed mothers. Of the rest only one stemmed from the female-specific burden of carrying a child in the womb: “medically diagnosable harm” during pregnancy.

The other detriments are gender-neutral, bearing on the anticipated burdens of raising a child, a matter in which mothers have no monopoly. These burdens of child-rearing included (in Roe’s words) the prospect that “[m]aternity, or additional offspring, may force upon the woman a distressful life and future.” In addition,

Psychological harm may be imminent. Mental and physical health may be taxed by child care. There is also the distress, for all concerned, associated with the unwanted child, and there is the problem of bringing a child into a family already unable, psychologically and otherwise, to care for it.

The challenges of raising children are quite real. But what makes them real is that they do not go away at birth, and no one would maintain that the challenges justify killing an infant. Further, since the challenges are not gender-specific, men often have just as good reasons—often, the same reasons—to avoid parenthood. Roe thus possesses few resources to develop a response to feticide defendants’ constitutional challenges. Indeed, it would not even help in answering infanticide defendants.

These defendants desire equal protection for themselves. Justified use of force must be available to all on equal terms; if the law permits lethal force against a class of persons who pose a threat, then lethal force should also be available to others who are threatened in the same way by the same people. Moreover, the law cannot constitutionally undermine the consistent application of homicide law by tinkering with the moral status of the homicide victim. If the feticide defendant has unjustly killed a human person, then so too has a pregnant woman who procures an abortion.

Courts have so far not attempted to resolve these grave questions; they have so far denied the feticide defendants’ appeals, with little more articulated reason than the obvious fact that granting these claims would rattle the structure of abortion rights in place since 1973. So they might. There is no guarantee that the abortion postulate can be maintained without incoherence. On pain of consistency, the courts must consider the consequences of a fetal right to life, and this is to ask Thomson’s question.

Suppressing Thomson’s question is risky as a short-term strategy. In the long run it will not do at all. As the truth about unborn persons lodges itself more securely in our law and culture, the gravely anomalous character of abortion rights will become more, not less, obvious and disturbing. Forcing Thomson’s question and showing the contradictions in America’s laws is what pro-life legislation and litigation must do in the future.