State v. Moore

A trial court may declare a mistrial, in spite of double jeopardy, if there is a "manifest necessity" to do so.

Defendant sought a writ of mandamus directing the trial court to dismiss the indictment against him, with prejudice, based on federal and state double jeopardy. Subsequent to a key witness being discovered mid-trial, a co-defendant moved for a mistrial. Defendant objected, but the trial court granted the mistrial, finding it was a “manifest necessity” in the interest of justice. Defendant argued that he was entitled to complete his trial with the jury selected and that the State had not met the “manifest necessity” standard. The State argued the trial court was simply exercising its discretion to avoid undue prejudice on Defendant by allowing the evidence in mid-trial. A trial court may declare a mistrial if there is a "manifest necessity" to do so. The Court found two reasons why the State had not met the “manifest necessity” standard. First, the State should not have proceeded to trial without the key witness. Second, it is significant that the State examined, and defense counsel cross-examined, eight witnesses for the State prior to the mistrial. That fact presented a significant potential for prejudice to Defendant and an unfair advantage to the State. For those reasons, the Court concluded that the trial court’s sua sponte mistrial order violated Defendant’s right to be free from a second prosecution for the same offense under Article I, section 12, of the Oregon Constitution. Peremptory writ of mandamus issued.