During a fight with his estranged girlfriend, D shot and killed their 20-day-old daughter. D was convicted of second-degree murder. D sought post-conviction relief. By 1986, he had filed five state petitions, all of which were denied. He filed a federal habeas petition, which was unsuccessful as well. After the Supreme Court's decision in Cage, D stated a new round of petitions. The jury instruction defining reasonable doubt at D's trial was substantively identical to the instruction condemned in Cage, D filed a sixth state post-conviction petition, this time raising a Cage claim. The State District Court denied relief, and the Louisiana Supreme Court affirmed. D returned to federal court. D filed for permission to file a second habeas corpus application. The Court of Appeals held that D must make made 'a prima facie showing,' that his 'claim relies on a new rule of constitutional law, made retroactive to cases on collateral review by the Supreme Court, that was previously unavailable.' The Court of Appeals granted the motion. The District Court held that, although Cage should apply retroactively, D was not entitled to collateral relief. Under AEDPA, a state prisoner can prevail only if the state court's decision 'was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States.' The Court of Appeals affirmed. D could not show that any Supreme Court decision renders the Cage decision retroactively applicable to cases on collateral review. The Supreme Court granted certiorari.