1987 Constitution of the Philippines
Section 1. The judicial power shall be vested in one Supreme Court and in such lower courts as may be established 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 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.