“In R. v. White, 1947 CanLII 1 (SCC), [1947] S.C.R. 268, at p. 272, the Supreme Court of Canada discussed the inexact science of weighing a witness’ credibility:
It is a matter in which so many human characteristics, both the strong and the weak, must be taken into consideration. The general integrity and intelligence of the witness, his power to observe, his capacity to remember and his accuracy in statement are important. It is also important to determine whether he is honestly endeavouring to tell the truth, whether he is sincere and frank or whether he is biased, reticent and evasive.
In Christakos v. De Caires, 2016 ONSC 702 (CanLII), 2016 CarswellOnt 1433, at para. 10, I summarized some aspects of the credibility assessment as set out in Re Novak Estate, 2008 NSSC 283 (CanLII), 269 N.S.R. (2d) 84, at paras. 36-37:
There are many tools for assessing credibility:
a) The ability to consider inconsistencies and weaknesses in the witness’ evidence, which includes internal inconsistencies, prior inconsistent statements, inconsistencies between the witness’ testimony and the testimony of other witnesses.
b) The ability to review independent evidence that confirms or contradicts the witness’ testimony.
c) The ability to assess whether the witness’ testimony is plausible or, as stated by the British Columbia Court of Appeal in Faryna v. Chorny, 1951 CanLII 252 (BC CA), 1951 CarswellBC 133, it is “in harmony with the preponderance of probabilities which a practical [and] informed person would readily recognize as reasonable in that place and in those conditions”, but in doing so I am required not to rely on false or frail assumptions about human behaviour.
d) It is possible to rely upon the demeanour of the witness, including their sincerity and use of language, but it should be done with caution ( v. Mah, 2002 NSCA 99 (CanLII) [at paras.] 70-75).
e) Special consideration must be given to the testimony of witnesses who are parties to proceedings; it is important to consider the motive that witnesses may have to fabricate evidence. v. J.H.,2005 CanLII 253 (ON CA), [2005] O.J. No.39 (OCA)[at paras.] 51-56). There is no principle of law that requires a trier of fact to believe or disbelieve a witness’ testimony in its entirety. On the contrary, a trier may believe none, part or all of a witness’ evidence, and may attach different weight to different parts of a witness’ evidence. (See R. v. D.R. 1996 CanLII 207 (SCC), [1996] 2 S.C.R. 291 at [para.] 93 and R. v. J.H. supra). [Emphasis omitted.]”