The High Court exercises both original jurisdiction and appellate jurisdiction in civil and criminal matters. By possessing original jurisdiction, the Court is able to hear cases at first instance – it can deal with trials of matters coming before the courts for the first time. A special aspect of the Court's original jurisdiction is its judicial review jurisdiction, under which it determines the constitutionality of legislation and actions taken by the Government. The Court exercises its appellate jurisdiction when it hears appeals from trials originating in the Subordinate Courts such as District Courts and Magistrates' Courts. The Court also exercises supervisory and revisionary jurisdiction over subordinate courts. The exercise of judicial review of administrative acts carried out by public authorities to ensure that they comply with principles of administrative law is an aspect of the Court's supervisory jurisdiction.