The Supreme Court recently granted certiorari in Montgomery v. Louisiana to determine whether the Court’s holding in Miller v. Alabama, that “the Eighth Amendment forbids a sentencing scheme that mandates life in prison without possibility of parole for juvenile offenders,” applies retroactively to cases on collateral review. That question is important in its own right, as we have previously discussed. But the Court also ordered argument on an additional, threshold question—one that, although perhaps less “sexy” than the merits question, may have profound implications for the scope of the Due Process Clause and retroactivity jurisprudence: Does the Supreme Court have jurisdiction over the case at all? That is, does Montgomery’s claim, which was nominally rejected on state law grounds by the Louisiana Supreme Court, even raise a federal question?