An appellate court is a court that hears cases in which a lower court -- either a trial court or a lower-level appellate court — has already made some decision, which at least one party to the action wants to challenge based upon some legal grounds that are allowed to be appealed either by right or by leave of the appellate court. A party who files an appeal is called an appellant, and a party on the other side is an appellee or, in some jurisdictions, a respondent. Cross-appeals can als