Binding Precedent (Stare Decisis)
Core rule: Courts are bound by the ratio decidendi of decisions made by courts above them in the hierarchy. Obiter dicta are persuasive only.
Court Hierarchy (binding effect)
- Supreme Court — binds all courts below. Can depart from its own previous decisions under the Practice Statement (Judicial Precedent) [1966] 1 WLR 1234 (House of Lords, now applied by the Supreme Court).
- Court of Appeal — binds the High Court and courts below; generally bound by its own decisions (Young v Bristol Aeroplane Co [1944] KB 718 — three exceptions: conflicting CA decisions; SC/HL decision implicitly overrules CA; per incuriam).
- High Court — binds inferior courts; not strictly bound by its own decisions, though strong persuasive weight.
- Crown Court / County Court / Magistrates' — not sources of binding precedent.
Ratio vs Obiter
- Ratio decidendi: the legal reasoning necessary to the decision — binding.
- Obiter dicta: remarks made by the way (e.g., hypotheticals, dissents) — persuasive only.
Techniques for Avoiding Precedent
- Distinguishing — finding a material difference of fact.
- Overruling — higher court disapproves the legal rule in an earlier case.
- Disapproving — court criticises but cannot overrule.
Persuasive Sources
- Privy Council decisions (highly persuasive).
- Scottish / Commonwealth courts.
- Strong obiter from the Supreme Court.
Common Traps
- Confusing overruling (changing the legal rule for the future) with reversing (changing the outcome on appeal in the same case).
- Assuming the Court of Appeal can freely depart from its own decisions — the Young v Bristol Aeroplane exceptions are narrow.
- The 1966 Practice Statement is used sparingly; the Supreme Court does not depart lightly.
Exam tip: In a single-best-answer question, always identify the court level first — precedent questions turn on hierarchy before anything else.