Begin with the significance of LAWRENCE v. TEXAS. Ask her whether that precedent points to the Court recognizing a constitutional right to same-sex marriage, making her make it clear why she thinks (if she does) that the definition of marriage is not left to the people acting through legislatures. Then work back to ROE, asking her if she thinks the Court’s effort to resolve the abortion controversy judicially was a failure, as many pro-choice advocates now do. The Court’s reasoning in PLANNED PARENTHOOD and LAWRENCE needs to be highlighted: The word liberty in the Due Process Clause of the Fourteenth Amendment was left vague or undefined by our Framers to allow it to be used as a weapon by each generation of Americans--really, by the Court--for what amounts to the invention of new rights or the elitist resolution of controversial moral issues on which people reasonably disagree. The issue, for the Judiciary Committee, shouldn’t be being for or against the "choice" position on abortion or being for or against same-sex marriage. It is, in a way, about the right of citizens to be both for and against under our Constitution and to have their voices heard in the making of laws. Because the president has voiced his personal opposition to same-sex marriage, she should be asked whether she regards his view as having the same constitutional status as that of a segregationist.
The word "liberty" in the Due Process Clause of the Fourteenth Amendment wasn't even written by our Framers - that is, the men who drafted the US Constitution and later the Bill of Rights. It was ratified by three-fourths of the States and adopted on July 9, 1863, seventy-two years after the Bill of Rights came into effect. So, its highly unlikely that the leading Framers - Adams, Madison, Jay, Hamilton, Jefferson, et al. - intended it "to be used as a weapon by each generation... for what amounts to the invention of new rights or the elitist resolution of controversial moral issues on which people reasonably disagree." A more probable explanation is that it was intended to protect blacks and ex-slaves, particularly those in the South, against racial discrimination following the Civil War.