In dealing with the issue of circumstantial evidence in Manitoba Housing Authority (2012), 221 L.A.C. (4th) 186 (Gibson), arbitrator Gibson commented as follows:
The fact that evidence is circumstantial does not necessarily weaken its probative value. As stated by Arbitrator Hamilton in Boeing Canada Technology Ltd. … (2005), 145 L.A.C. (4th) 225 (Man. Arb. Bd.):
The fact that much of the evidence is circumstantial in nature is not fatal to the Company’s position because, in civil cases, circumstantial evidence is treated like any other kind of evidence, with the weight to be accorded to it being dependent on the strength of the inference that can be drawn therefrom. This is a task for the trier of fact. If there is insufficient circumstantial evidence pointing to the Grievor’s culpability then a finding in favour of the Company is not warranted …
It is well accepted that where the evidence against an employee is (primarily) circumstantial and where the offence must be proved on the “… clear convincing and cogent standard” a cautious approach must be taken when analyzing the circumstances because they must not only be consistent with guilt but must also be inconsistent with any other plausible explanation.
Arbitrator Gibson commented that Arbitrator Hamilton went on to say, at page 265 of Boeing:
There are numerous authorities which state that it is not an arbitrator’s task to “… solve the mystery” where circumstances are suspicious. Rather, it is the arbitrator’s task to determine whether the Company has established, on the applicable standard of proof, and after considering the evidence in its totality, that the Grievor committed the acts of which he is accused.
… Arbitrators have used different words to articulate the key tests. In many cases, a critical element has been a finding that a particular employee is culpable because he was the only person with a reasonable opportunity to do the act complained of, or was the only person in control of the situation(s). In this scenario, an onus of explanation will be cast on the Grievor to provide a reasonably plausible explanation.
Arbitrator Gibson found that certain of the explanations given by the employee in this case were not reasonably or inherently probable and that the employer had therefore proven its case based on the circumstantial evidence that it tendered.
Arbitrator Hamilton’s comments referenced an offence that must be proven “on a clear, convincing and cogent standard.” Since those comments were made, the Supreme Court of Canada has clarified the onus in civil cases, stating, in a 2008 decision, that:
I think it is time to say, once and for all in Canada, that there is only one civil standard of proof at common law and that is proof on a balance of probabilities. Of course, context is all important and a judge should not be unmindful, where appropriate, of inherent probabilities of the seriousness of the allegations or consequences. However, these considerations do not change the standard of proof.
… Similarly evidence must also be sufficiently clear, convincing and cogent to satisfy the balance of probabilities test..
The issue of onus as it applies to the various categories of illness and absenteeism is dealt with in Chapter 6 of the Illness and Absenteeism manual.