R v Darrach – (2000) 2 SCR 443 (Gonthier):

[24] These cases are part of the Court’s jurisprudence that has consistently held that the principles of fundamental justice enshrined in s. 7 protect more than the rights of the accused. As McLachlin J. wrote in Seaboyer, supra, at p. 603: “ The principles of fundamental justice reflect a spectrum of interests, from the rights of the accused to broader societal concerns…. The ultimate question is whether the legislation, viewed in a purposive way, conforms to the fundamental precepts which underlie our system of justice.”

One of the implications of this analysis is that while the right to make full answer and defence and the principle against self-incrimination are certainly core principles of fundamental justice, they can be respected without the accused being entitled to “the most favourable procedures that could possibly be imagined” (R. v. Lyons, [1987] 2 S.C.R. 309, at p. 362; cited in Mills, supra, at para. 72). Nor is the accused entitled to have procedures crafted that take only his interests into account. Still less is he entitled to procedures that would distort the truth-seeking function of a trial by permitting irrelevant and prejudicial material at trial.