When a jury expressly states it is 'unable to agree' on a defendant's guilt for a greater offense and convicts the defendant of a lesser offense, and the defendant successfully appeals his conviction, does the hung jury rule permit retrial of the greater offense or does Green instead bar retrial of that offense?

QUESTION PRESENTED In Green v. United States, the Court held that the Double Jeopardy Clause barred retrial of a greater offense when the jury’s “verdict was silent” on that offense. 355 U.S. 184, 186, 190-91 (1957). In Richardson v. United States, the Court affirmed that the hung jury rule permits retrial of an offense on which the jury was unable to agree. 468 U.S. 317, 324 (1984). Here, a jury convicted respondent, Philip Martin, of second-degree murder. In its verdict, the jury stated it was “unable to agree” on the greater, first-degree murder charge. Martin successfully appealed, and his conviction was reversed. On remand, the State again sought—and obtained—a first-degree murder conviction. The Arizona Supreme Court vacated the conviction, holding the Double Jeopardy Clause barred Martin’s retrial for first-degree murder under Green. The question presented, upon which courts are divided, is: When a jury expressly states it is “unable to agree” on a defendant’s guilt for a greater offense and convicts the defendant of a lesser offense, and the defendant successfully appeals his conviction, does the hung jury rule permit retrial of the greater offense or does Green instead bar retrial of that offense? ii STATEMENT OF