ratio decidendi

The ratio decidendi is the rule of law that was necessary for the decision, read with the material facts. It is what binds courts below (and co-ordinate benches) under the doctrine of precedent. Under Article 141 of the Constitution, the law declared by the Supreme Court binds all courts in India, and “law declared” means the ratio.

Everything said by the way, not needed for the result, is obiter dictum: persuasive, sometimes highly so, but not binding. Finding the ratio is a matter of reading the judgment: Wambaugh's inversion test asks whether the decision would change if the proposition were reversed; Goodhart's test looks at the material facts and the decision on them. A decision given sub silentio or per incuriam has no binding ratio on the point missed.

Example

The ratio decidendi of Maneka Gandhi is that a procedure under Article 21 must be fair, just and reasonable; the remarks on foreign travel generally were obiter.

In Indian law

• Article 141, Constitution of India (law declared by the Supreme Court binding on all courts)

See also

obiter dicta · stare decisis · precedent · per incuriam

Read more in the study notes

• Administrative law: meaning, nature, scope, growth and sources (Administrative Law)
• Separation of powers and its bearing on administrative law (Administrative Law)
• Rule of law and droit administratif (Administrative Law)
• Classification of administrative action (Administrative Law)
• Excessive delegation, conditional legislation and sub-delegation (Administrative Law)
• Control of delegated legislation: parliamentary, procedural and judicial (Administrative Law)