Administrative Code of 1987
Section 16. Judicial Power. - The judicial power shall be vested in one (1) Supreme Court, and in such lower courts as may be established by law. Such lower courts include the Court of Appeals, Sandiganbayan, Court of Tax Appeals, Regional Trial Courts, Shari's District Courts, Metropolitan Trial Courts, Municipal Trial Courts and Municipal Circuit Trial Courts, and Shari'a Circuit Courts and they shall continue to exercise their respective jurisdiction until otherwise provided by law.
Judicial power includes the duty of the courts of justice to settle actual controversies involving rights which are legally demandable and enforceable, and, in cases prescribed by law, to determine whether or not there has been a grave abuse of discretion amounting to lack or excess of jurisdiction on the part of any branch or instrumentality of the Government.