In C.H. Giles & Co. Ltd. v. Morris,  1 W.L.R. 307,  1 All E.R. 960 at 971 (Ch.D., Megarry J.) said:
… In this judgment I have referred to a number of authorities not cited in argument. On the procedural point I have reached no final conclusion, and so the citation of additional authorities in that respect does not raise any particular difficulty. But it is otherwise in relation to the question of specific enforceability. On this, the only authority cited to me by either side was Fry, cited by counsel for the defendants. Wilson v West Hartlepool Railway Co came into the picture because looking at Snell’s Equity during the argument, I found the case cited there on what seemed to be the relevant point, and I drew counsel for the plaintiffs’ attention to it; and at the conclusion of leading counsel for the plaintiffs’ argument his junior read me certain passages from the case in support of the plaintiffs’ cause. The case was thus both mentioned and cited before counsel for the defendants began his reply; and at an earlier stage I had put questions to him based on there being a distinction between a contract for personal services and a contract to enter into a contract for personal services. At the conclusion of the argument, I intimated that I might require further argument, particularly as my copy of the report of Wilson’s case showed that the decision had been referred to in a number of subsequent cases. I have not pursued these references, and find that they relate to issues in Wilson’s case other than that of the specified enforceability of the agreement. In those circumstances, I have not thought it right to involve those concerned in the trouble and delay that would result from restoring the case for further argument. The point and the leading authority on it were fairly before counsel, and the other authorities seem to me in the main merely to support and amplify that authority. Indeed, Granville v Betts, Stocker v Wedderburn and Wilson v Wilson were all cited in Wilson’s case. Fortescue’s case, it is true, exemplifies a different aspect, but even if in some way it could be shown to be nihil and rem, that would not destroy either the authority of Wilson’s case or the principle. Fortescue’s case, I may say, is duly cited in Fry, two pages on from the passage which counsel for the defendants cited to me. I am dealing explicitly with this point because, of course, this is a committal case, with all that that implies, and the citation in a judgment of authorities not discussed during argument is a matter that must be approached with caution. Accordingly, although I do not require further argument, if counsel on either side desire that there should be any further argument, I shall readily listen to any application for the purpose.
The process of adjudication is characterized by the right of the parties to present proofs and reasoned arguments. This right presupposes that, inter alia, the standards of reasoned argument are known and that the judge will not consider points on which counsel have not had an opportunity to present either proofs (of facts) or to make representations on the law.
Megarry J. obviously takes the need to protect this right very seriously. I wonder how many Canadian judges would be so careful.
Perhaps the larger question is whether judges today should be so careful and, if they are not, what the consequences are.