What is the current state of the law on the reliability of opinion evidence?

[75] Needless to say there is a continuum of reliability in matters of science from near certainty in physical sciences to the far end of the spectrum inhabited by junk science and opinion akin to sorcery or magic. Whether the technique can be demonstrably tested, the existence of peer review for the theory or technique, the existence of publication, the testing or validation employing control and error measurement, and some recognition or acceptance in the relevant scientific field all contribute to an assessment of the reliability of the opinion and hence its capacity to outweigh the prejudicial impact of imposing on the jury highly suspect opinion evidence masquerading as science. See also The Queen v. J.J., [2000] 2 S.C.R. 600, 2000 SCC 51, 261 N.R. 111, 192 D.L.R. (4th) 416, 148 C.C.C. (3d) 487, 37 C.R. (5th) 203, [2000] S.C.J. No. 52, 2000 Cars­well­Que 2310.