Formal request that a higher court hear a case that has been decided in a lower court. State Supreme Courts are the highest courts which can hear appeals for cases involving state law, while the US Supreme Court is the highest court which can hear appeals for cases involving federal or constitutional law. An court appeal to a state appellate court are generally made on procedural grounds, i.e., on the basis that some aspect of proper legal procedure was not observed in the original trial. Anyone can petition the US Supreme Court to take a case under advisement. However, the Court is only likely to accept a case if it involves issues related to the constitutionality of the lower court's decision, or state versus federal powers.