(2) The decisions of superior courts in other portions of the British Empire, for example, the Irish courts.[[156]]
(3) The judgments of the Privy Council when sitting as the final court of appeal from the Colonies.[[157]]
(4) Judicial dicta, that is to say, statements of law which go beyond the occasion, and lay down a rule that is irrelevant or unnecessary for the purpose in hand. We shall see later that the authoritative influence of precedents does not extend to such obiter dicta, but they are not equally destitute of persuasive efficacy.[[158]]
§ 64. The Absolute and Conditional Authority of Precedents.
Authoritative precedents are of two kinds, for their authority is either absolute or conditional. In the former case the decision is absolutely binding and must be followed without question, however unreasonable or erroneous it may be considered to be. It has a legal claim to implicit and unquestioning obedience. Where, on the other hand, a precedent possesses merely conditional authority, the courts possess a certain limited power of disregarding it. In all ordinary cases it is binding, but there is one special case in which its authority may be lawfully denied. It may be overruled or dissented from, when it is not merely wrong, but so clearly and seriously wrong that its reversal is demanded in the interests of the sound administration of justice. Otherwise it must be followed, even though the court which follows it is persuaded that it is erroneous or unreasonable. The full significance of this rule will require further consideration shortly. In the meantime it is necessary to state what classes of decisions are recognised by English law as absolutely, and what as merely conditionally authoritative.
Absolute authority exists in the following cases:—
(1) Every court is absolutely bound by the decisions of all courts superior to itself. A court of first instance cannot question a decision of the Court of Appeal, nor can the Court of Appeal refuse to follow the judgments of the House of Lords.
(2) The House of Lords is absolutely bound by its own decisions. “A decision of this House once given upon a point of law is conclusive upon this House afterwards, and it is impossible to raise that question again as if it was res integra and could be re-argued, and so the House be asked to reverse its own decision.”[[159]]
(3) The Court of Appeal is, it would seem, absolutely bound by its own decisions and by those of older courts of co-ordinate authority, for example, the Court of Exchequer Chamber.[[160]]
In all other cases save these three, it would seem that the authority of precedents is merely conditional. It is to be noticed, however, that the force of a decision depends not merely on the court by which it is given but also on the court in which it is cited. Its authority may be absolute in one court, and merely conditional in another. A decision of the Court of Appeal is absolutely binding on a court of first instance, but is only conditionally binding upon the House of Lords.