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Jurisprudence · Unit 2

Sources of Law

Unit 2 of Jurisprudence / Legal Theory (syllabus: Module II — formal and material sources; custom, its kinds and the conditions of its validity, and trade usage; precedent, stare decisis, prospective overruling, the declaratory theory, ratio decidendi and obiter dicta, the circumstances that destroy binding force, and the merits and demerits of precedent; legislation, its kinds, merits and demerits, codification and statutory interpretation; and convention). Below: what the unit covers, the provisions it turns on, and the cases an examiner expects you to name.

What this unit covers

  • Distinguish the formal, material, historical and legal sources of law.
  • What are the essential conditions of a valid custom?
  • How is a precedent classified, and what turns on the classification?
  • What is the ratio decidendi, and how is it distinguished from obiter dictum?
  • State the three tests for finding the ratio decidendi.
  • What circumstances destroy the binding force of a precedent?
  • Distinguish supreme, subordinate and delegated legislation, and state the controls over delegation.
  • State the principal rules of statutory interpretation.

Treat that list as a self-test: recite each topic's rule from memory before you open its cases.

Leading cases

  • Salmond
  • Salmond and Keeton
  • Union of India v K.S. Subramanian
  • State of Orissa v Sudhanshu Shekhar Mishra
  • Goodhart
  • A.R. Antulay v R.S. Nayak on per incuriam
  • Salmond and Gray on the definition of legislation
  • Heydon's Case

Exam questions on this unit