Certainty in judicial practice

STARE decisis et non quieta movere, meaning "stand by the decisions and disturb not what is settled," is a doctrine rooted in the necessity of stability, certainty and predictability in judicial decisions. Stare decisis is based on the rule that "once a question of law has been examined and decided, it should be deemed settled and closed to further argument" (De Mesa v Pepsi Cola Products Phils. Inc., GR Nos. 153063-70, Aug. 19, 2005). It stems from the principle of justice that "absent any powerful countervailing considerations, like cases ought to be decided alike" (Commissioner of Internal Revenue v The Insular Life Assurance Co. Ltd., GR 197192, June 4, 2014).

Under the Constitution, the Supreme Court is the final arbiter of controversies involving rights that are legally demandable and enforceable. Article 8 of the New Civil Code, meanwhile, provides that "judicial decisions applying to or interpreting the laws or the Constitution shall form a part of the legal system of the Philippines." To be clear, stare decisis applies only to cases decided by the Supreme Court.