Ratio decidendi

The traditional doctrine of precedent in English common law has been that a precedent which is binding is binding only as to its ratio decidendi, that is, its 'rule of decision'. Only this is strictly authoritative for the future, and any explanatory or argumentative statements by the court or individual judges are deemed 'obiter dicta', persuasive according to their cogency and relevancy, but not binding in law. The same applies in Northern Ireland. In Scots law, it has been argued on high authority (Smith, 1952) that the difference of legal tradition has generated both a broader conception of ratio decidendi, to include general principles rather than more particular rules of decision, and a somewhat less strict view of the binding quality of individual precedents. (s.336, Interpreting Precedents, United Kingdom)