Legal Definitions - anomalous-jurisdiction rule

The anomalous-jurisdiction rule is a principle that states that a court of appeals has temporary jurisdiction to review the denial of a motion to intervene in a case. If the court of appeals finds that the denial was correct, then its jurisdiction disappears, and it must dismiss the appeal for want of jurisdiction because an order denying a motion to intervene is not a final, appealable order.

For example, if a person wants to join a lawsuit as a party but the trial court denies their motion to intervene, they can appeal that decision to the court of appeals. However, if the court of appeals agrees with the trial court's decision, then the court of appeals must dismiss the appeal because it no longer has jurisdiction over the case.

Many appellate courts have criticized this rule because it can lead to confusion and delays in the legal process. Some courts will instead affirm the denial of the motion to intervene instead of dismissing the appeal for want of jurisdiction.