Williams v. Kallis

Issue: Whether an act of Congress, a court decision declaring a new rule of constitutional law or a court decision establishing a new rule of statutory construction is the type of change in the law that allows a person convicted of a federal offense to file a petition to challenge their convictions pursuant to 28 U.S.C. § 2241; and (2) whether the decision in Mathis v. United States was a change in the law regarding whether a prior state robbery conviction is a crime of violence.