What constitutes “non-expert opinion evidence” in identification evidence at trial?

The identification evidence offered by the police officers was “non-expert opinion evidence”. Such evidence is often relevant and admissible to prove identification when the trier of fact is not in a position to make the identification unaided. In a wiretap situation, for example, the accused is under no obligation to speak at trial, it is, therefore, not possible for the judge or the jury to compare the voice of the accused with the voice on the intercepted communication. In these situations, the opinion evidence of non-experts is admitted to assist the trier of fact in determining identification. The witness must be shown to have the special knowledge that the court does not possess. The admission of such opinion evidence is always subject to one important qualification, stated by Dickson J. (as he then was) in Graat v. The Queen (1982) 1982 CanLII 33 (SCC), 2 C.C.C. (3d) 365; 31 C.R. (3d) 289; [1982] 2 S.C.R. 819; 144 D.L.R. (3d) 267 (at p. 281): “If the court is being told that which it is in itself entirely equipped to determine without the aid of the witness on that point then of course the evidence is supererogatory and unnecessary. It would be a waste of time listening to superfluous testimony.”