The simple argument
The first argument is something we hear all the time: "Women have a right to control their own bodies." Or: "It's my body, I'll decide."
These claims beg the question, or simply assume the pro-choice conclusion without actually giving reasons for it. Namely, they assume only one body is involved, and thus that abortion is not the killing of a separate, valuable human person.
The science of embryology tells us that the unborn is its own whole organism, genetically and functionally distinct from (though living inside of) the woman. A pro-choice advocate could argue that this unborn human being is not yet a "person" or a subject of rights, but that's the real issue at hand (whether or not the unborn has a right to life). The issue is not "a woman's right to control her body," for the body at stake is not hers.
Peter Kreeft observes, "If the fetus is a part of the mother, then the parts of the fetus must be parts of the mother. But in that case, every pregnant woman has four eyes and four feet, and half of all pregnant women have penises! Clearly, the absurd conclusion came from the false premise that the fetus is only part of the mother."
Crux of the debate
Most sophisticated defenders of abortion do not make question-begging claims, and instead give reasons for their view that the unborn human is not a valuable, rights-bearing person. Thus the primary substantive debate over abortion has been on the moral status of unborn: pro-life advocates contend that human beings are intrinsically valuable, and so all humans have a right to life, irrespective of stage of development or cognitive functions; pro-choice advocates say that human beings only become valuable when they acquire certain properties that are deemed morally relevant (like the immediate capacity for self-awareness), and these criteria exclude the human embryo and fetus, who may therefore be killed by abortion. (For more on this debate, go here and here.)
The sophisticated argument
But other sophisticated defenders of abortion have taken a different approach. They concede, for the sake of argument, the pro-life view of the unborn (i.e., that the unborn is a valuable human person with a right to life), but then argue that abortion is still morally permissible. This is the second argument from bodily autonomy.
The basic claim is that a pregnant woman has no moral obligation to let the unborn human being use her body for sustenance and protection, just as she would have no obligation to let any other person use her body in that way. Thus, abortion is permissible. The argument was introduced by philosopher Judith Jarvis Thomson in a 1971 journal article (she used a famous thought experiment to make her case), and versions of it have since been defended by academics such as Eileen McDonagh and David Boonin.
I won't address the argument in detail, but let me highlight a few problems. Apart from cases in which pregnancy is a result of rape or incest, a woman is responsible for the sexual activity that leads to pregnancy. It seems reasonable to say that she bears some sort of responsibility for the vulnerable human being whose existence and dependency on his mother are a natural result of the woman's own choice. (Of course the father also bears responsibility.) And that would make the bodily autonomy argument, at best, only effective in cases of rape and incest -- less than one percent of Minnesota abortions.
Second (and I think this stems from the first point), the argument from bodily autonomy does not take into account the parent/child relationship: Parents seem to have a special obligation to their dependent offspring, and unborn children seem to have a rightful claim to the womb in which they grow. As philosopher Stephen Schwarz puts it, a mother "does have an obligation to take care of her child, to sustain her, to protect her, and especially, to let her live in the only place where she can now be protected, nourished, and allowed to grow, namely the womb."
This idea (that parents have unique responsibilities to their children) is well-reflected in our laws. Estranged fathers are required to pay child support, even if they never desired to be a father. If I abandon and let starve to death my two-year-old daughter, I will go to prison -- it simply will not work to say that my daughter is not entitled to my care and resources.
Francis Beckwith writes, "Most people ... agree that in ordinary circumstances a born child has a natural moral claim upon her parents to care for her, regardless of whether her parents 'wanted' her. This is why we prosecute child abusers and parents who abandon their children." If -- as proponents of the sophisticated bodily autonomy argument concede -- the unborn is a valuable person, like a born child, then the same parental obligation that applies after birth would seem to apply before.
Third, we seem to have some obligations as members of a community to persons who are weak, vulnerable and defenseless -- even if we are not related to them and are not responsible for their existence. Judge John T. Noonan relates the story of a Minnesota court case that makes this point well:
On a January night in Minnesota, a cattle buyer, Orlando Depue, asked a family of farmers, the Flateaus, with whom he had dined, if he could remain overnight at their house. The Flateaus refused and, although Depue was sick and had fainted, put him out of the house into the cold night. Imposing liability on the Flateaus for Depue's loss of his frostbitten fingers, the court said: "In the case at bar defendants were under no contract obligation to minister to plaintiff in his distress; but humanity demanded they do so, if they understood and appreciated his condition. ... The law as well as humanity required that he not be exposed in his helpless condition to the merciless elements." ... The American Law Institute, generalizing, has said that it makes no difference whether the person is a guest or a trespasser. He has the privilege of staying. His host has the duty not to injure him or put him into an environment where he becomes nonviable. The obligation arises when one "understands and appreciates" the condition of the other.Fourth, abortion is usually not a case of "unplugging" the unborn human being from his or her mother, as an analogy used by Thomson suggests. Rather, it is direct, intentional killing, often by dismemberment. There is a significant moral difference. If a stranger has been surgically connected to my body -- against my will -- in order for him to survive, perhaps I may legitimately "disconnect" him and withhold life support, predictably (but not with intention) resulting in his death. But clearly I may not use a machete to chop him into pieces.
Even if a pregnant woman has no responsibility or obligation to the unborn, abortion does not seem to be justified, because it is the intentional killing of an innocent human being.
Turning justice on its head
For these and other reasons, I think the bodily autonomy argument fails completely. Conceding the full dignity and rights of the unborn is a startling admission, and it's impossible for a defender of abortion to recover. But I would go further: I would suggest that the special circumstances of pregnancy actually make abortion worse than other forms of homicide (rather than, as the bodily autonomy proponent claims, a justified form of homicide). I'll explain in a future post.
For much more pro-life criticism (both popular and scholarly) of this argument, see "The Case for Life" by Scott Klusendorf (Chapter 15), "Defending Life" by Francis Beckwith (Chapter 7) and "Abortion and Unborn Human Life" by Patrick Lee (Chapter 4). Also see online essays addressing the argument here, here and here.