The doctrine of precedent, also known as stare decisis, is a fundamental principle in common law jurisdictions. Under this doctrine, lower courts are bound by the decisions of higher courts in similar cases. This ensures consistency and predictability in the legal system. Precedent can be either binding or persuasive. Binding precedent must be followed by lower courts, while persuasive precedent is not binding but may be considered in reaching a decision. The hierarchy of courts plays a crucial role in determining the precedential value of a decision. There are exceptions to the doctrine of precedent, such as when a previous decision was made per incuriam (in error) or is no longer relevant due to changes in the law. Additionally, courts can distinguish a case from a previous decision if there are material differences. Overall, the doctrine of precedent serves to promote fairness, equality, and efficiency in the legal system. By respecting and applying prior decisions, courts ensure a degree of continuity and coherence in the development of case law.