Mootness on Appeal

Courts can generally only render an opinion or judgment when there is actually a controversy in a case. Legally, this means that a party filing a lawsuit must have “standing” and there must be a “justiciable” controversy. This  exists when a party has an interest in the subject matter of the suit that gives it a right to recovery, if validated. Midwestern Health Mgmt., Inc. v. Walker, 208 S.W.3d 295, 298 (Mo. Ct. App. 2006).
While the question of “standing” is often raised immediately at the trial court level, it can also arise on appeal, particularly if something happens during the litigation which renders the controversy moot. When an event occurs that makes a court’s decision unnecessary or make granting effectual relief by the court impossible, the case is moot and should generally by dismissed. Kinsky v. Steiger, 109 S.W.3d 194, 195 (Mo. Ct. App. 2003). In short, courts do not render hypothetical opinions if factual circumstances have changed to where there it is no longer a dispute. 
There are two exceptions to this rule. The first is when the case becomes moot after the matter is submitted for decision to the appellate court. In other words, once the matter is fully briefed, argued and given to the court of appeals for consideration, the court of appeals will make the decision even if there is a change in factual circumstances. The second is when the issue raised has general public interest and importance, and is likely to recur and will otherwise evade appellate review. Both of these exceptions are interpreted and applied narrowly by courts. 
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