ratio decidendin.

1689 in W. H. Bryson & S. Dauchy Ratio Decidendi (2006) I. 124 The arguments and rationes decidendi set out at length, the reporters thus assuming the function now of advocate, now of judge.

1714 W. Forbes Jrnl. Session 1705–13 16 But that Difference was not the Ratio decidendi, nor had any Influence upon the Decision.

1759 J. Maclaurin Observ. Points of Law xviii. 57 It is easy to see, why the Lord Stair approves of the decision; yet he condemns the ratio decidendi, in the case of Aikmans.

1829 Edinb. Advertiser 4 Dec. 773/1 That the decisions in Falkland and Linlithgow have been decided on principles adverse to the pursuer's claim, in respect the ratio decidendi in the first of these, adopted also in the second, was, that Falkland Park was still a royal demesne.

1862 in C. Clark House of Lords Cases VIII. 392 The observations made by Members of the House, whether law Members or lay Members beyond the ratio decidendi which is propounded and acted upon in giving judgment, although they may be entitled to respect, are only to be followed in as far as they may be considered agreeable to sound reason and to prior authorities.

1877 Law Rep.: Exchequer Div. 2 233 The ratio decidendi in these cases does not appear in the reports.

1902 J. W. Salmond Jurisprudence viii. 176 A precedent, therefore, is a judicial decision which contains in itself a principle. The underlying principle which thus forms its authoritative element is often termed the ratio decidendi.

1948 Law Q. Rev. 64 463 The court is always at liberty to propound alternative rules of law, each of which it may elevate to the status of a ratio decidendi.

1970 Internat. & Compar. Law Q. 19 i. 37 Which of these rationes decidendi possesses binding force?

1985 R. C. A. White Admin. of Justice iii. x. 170 This will reveal the reason for the decision, known among lawyers as the ratio decidendi of the case.