Marco Rubio, Mike Huckabee, and other politicians continue to assert a common fallacy about abortion—because human life begins at conception, fetuses are persons, and abortion must be prohibited. Indeed, Huckabee and Rubio claim that the U.S. Constitution requires such a result.
But they are wrong. And not just because people disagree about the beginning of personhood. The flaw in the Rubio/Huckabee logic was pointed out more than 40 years ago, even before the U.S. Supreme Court recognized a constitutional right to abortion in Roe v. Wade. In “A Defense of Abortion,” Professor Judith Jarvis Thomson correctly observed that even if we assume that personhood begins at conception, it does not follow that abortion must be banned before the fetus is viable. Indeed, as she wrote, a ban on abortion before fetal viability would be inconsistent with basic principles of law.