Judicial precedent: stare decisis, ratio decidendi and obiter dicta, the hierarchy of the courts, binding and persuasive precedent, and the ways judges can avoid precedent.

What this dot point is asking

AQA wants you to explain the doctrine of binding precedent, distinguish the ratio from obiter, set out the court hierarchy, and explain the mechanisms judges use to avoid a precedent. You should be able to evaluate precedent for certainty and flexibility.

The doctrine and the parts of a judgment

A judgment has two parts. The ratio decidendi is the principle of law on which the decision is based; it is the binding part. The obiter dicta are "things said by the way", such as comments on hypothetical facts; these are only persuasive. The famous obiter in R v Howe (that duress is no defence to attempted murder) became the binding ratio in R v Gotts.

The court hierarchy

Avoiding precedent

• The Practice Statement 1966 lets the Supreme Court depart from its own previous decisions when it is right to do so; it was first used in a civil case in Conway v Rimmer and in a criminal case in R v Shivpuri.
• The Court of Appeal is normally bound by its own decisions, but under Young v Bristol Aeroplane Co it may depart where there are conflicting past decisions, where its decision conflicts with a later Supreme Court decision, or where its earlier decision was made per incuriam (in error).
• Overruling is where a higher court states that the law in an earlier case is wrong. Reversing is where a higher court changes the decision of a lower court on appeal in the same case. Distinguishing is where a judge finds the material facts of the present case are different, so the earlier precedent does not apply, as in Balfour v Balfour and Merritt v Merritt.

A frequent exam task is to evaluate precedent. Its advantages are certainty (people can predict how the law applies and settle disputes accordingly), consistency and fairness (like cases treated alike), the capacity for flexibility through the Practice Statement and distinguishing, the precision of rules built from concrete facts, and time-saving once a point is settled. Its disadvantages are rigidity (a bad precedent may bind until a suitable case reaches a court able to depart from it, and litigants face the cost and delay of appealing), complexity (hundreds of thousands of reported cases make the law hard to find), the difficulty of isolating the ratio within a long judgment, and the unpredictability that judicial creativity can introduce. There is also a constitutional concern that unelected judges effectively make law, which feeds the wider debate on the separation of powers, although judges respond that they only develop the common law incrementally. A strong answer balances certainty against flexibility and concludes on whether the doctrine strikes the right balance.

How precedent is examined

Judicial precedent is examined through descriptive questions on the mechanics and evaluative questions on certainty against flexibility. Examiners reward correctly distinguishing ratio from obiter, accurately naming the avoidance mechanisms and the Young v Bristol Aeroplane exceptions, and a balanced conclusion.