An appellate court, commonly called an appeals court, court of appeals (American English),appeal court (British English), court of second instance or second instance court, is any court of law that is empowered to hear an appeal of a trial court or other lower tribunal. In most jurisdictions, the court system is divided into at least three levels: the trial court, which initially hears cases and reviews evidence and testimony to determine the facts of the case; at least one intermediate appellate court; and a supreme court (or court of last resort) which primarily reviews the decisions of the intermediate courts. A jurisdiction's supreme court is that jurisdiction's highest appellate court. Appellate courts nationwide can operate under varying rules.
The authority of appellate courts to review the decisions of lower courts varies widely from one jurisdiction to another. In some areas the appellate court has limited powers of review. Generally, an appellate court's judgment provides the final directive of the appeals courts as to the matter appealed, setting out with specificity the court's determination that the action appealed from should be affirmed, reversed, remanded or modified.
In the United States, both state and federal appellate courts are usually restricted to examining whether the lower court made the correct legal determinations, rather than hearing direct evidence and determining what the facts of the case were. Furthermore, U.S. appellate courts are usually restricted to hearing appeals based on matters that were originally brought up before the trial court. Hence, such an appellate court will not consider an appellant's argument if it is based on a theory that is raised for the first time in the appeal.
In most U.S. states, and in U.S. federal courts, parties before the court are allowed one appeal as of right. This means that a party who is unsatisfied with the outcome of a trial may bring an appeal to contest that outcome. However, appeals may be costly, and the appellate court must find an error on the part of the court below that justifies upsetting the verdict. Therefore, only a small proportion of trial court decisions result in appeals. Some appellate courts, particularly supreme courts, have the power of discretionary review, meaning that they can decide whether they will hear an appeal brought in a particular case.