Lett (defendant) was charged with murder. His murder trial lasted a total of less than nine hours. The jury deliberated for four hours and then sent a note to the judge saying: “What if we can’t agree? [M]istrial? [R]etrial? [W]hat?” The judge then called the jury back and asked: “Are you going to reach a unanimous verdict, or not?” The jury foreperson responded: “No, judge.” The judge declared a mistrial and discharged the jury. At Lett’s second trial for the murder, a different jury found him guilty after deliberating for three hours and 15 minutes. Lett appealed on double jeopardy grounds. The Michigan Supreme Court denied the appeal. Lett obtained a writ of habeas corpus from the federal district court, and the United States Court of Appeals for the Sixth Circuit affirmed. The United States Supreme Court granted certiorari to review.