On March 30, 2016, the Supreme Court heard oral argument in Welch v. United States. Police entered Gregory Welch’s apartment believing that a robbery suspect was on the premises, and after he consented to search they located a gun and ammunition that Welch later identified as his own. He was subsequently arrested and pleaded guilty to being a felon in possession of a firearm. Because Welch had three prior felony convictions, the district court determined that the Armed Career Criminal Act (ACCA) required that he be sentenced to a minimum of 15 years in prison. Welch appealed, arguing that his conviction for robbery in Florida state court did not qualify as a predicate offense for the purposes of ACCA because, at the time he was convicted, Florida state law allowed for a robbery conviction with a lower level of force than the federal law required to qualify as a predicate offense. The U.S. Court of Appeals for the Eleventh Circuit, however, affirmed the district court’s judgment, concluding that the minimum elements for conviction under the Florida law established a “serious risk of physical injury to another” and, therefore, qualified it as a predicate offense for purposes of ACCA. Welch’s subsequent attempt to obtain habeas relief from the district court was denied, and the Eleventh Circuit rejected his appeal, but the Supreme Court granted certiorari. -- The two questions before the Supreme Court are: (1) Whether Johnson v. United States, 135 S. Ct. 2551 (2015)—which held that the residual clause in the Armed Career Criminal Act of 1984 (ACCA), 18 U.S.C. 924(e)(2)(B)(ii), is unconstitutionally vague—announced a new “substantive” rule of constitutional law that is retroactively applicable in an initial motion to vacate a federal prisoner’s ACCA-enhanced sentence under 28 U.S.C. 2255(a); and (2) Whether petitioner’s conviction for robbery under Florida state law qualifies as a violent felony that supports a sentence enhancement under the ACCA. -- To discuss the case, we have Richard E. Myers II, who is the Henry Brandis Distinguished Professor of Law, University of North Carolina School of Law.