What is the standard of proof in a workplace investigation?

The standard of proof in a workplace investigation is a lower standard than criminal trials, for example. There is no presumption of innocence which is linked to the higher standard of a reasonable doubt.  

In an investigation, an investigator makes a determination on a balance of probabilities (“BOP”). A balance of probabilities means that it is more likely than not, a violation has occurred. It is the Complainant (or Applicant in a Human Rights Tribunal matter) that has the onus of proving, on a balance of probabilities, that a violation of the Human Rights Code or Occupational Health and Safety Act occurred.

What evidence will satisfy the BOP test?

The Supreme Court of Canada concluded in F.H. v. McDougall, 2008 SCC 53 (CanLII), [2008] 3 SCR 41:

“[… E]vidence must always be sufficiently clear, convincing and cogent to satisfy the balance of probabilities test.  But again, there is no objective standard to measure sufficiency.  In serious cases, like the present, judges may be faced with evidence of events that are alleged to have occurred many years before, where there is little other evidence than that of the plaintiff and defendant.  As difficult as the task may be, the judge must make a decision.  If a responsible judge finds for the plaintiff, it must be accepted that the evidence was sufficiently clear, convincing and cogent to that judge that the plaintiff satisfied the balance of probabilities test.”

….

“Where proof is on a balance of probabilities, there is no rule as to when inconsistencies in the evidence of a plaintiff will cause a trial judge to conclude that the plaintiff’s evidence is not credible or reliable.  The trial judge must not consider the plaintiff’s evidence in isolation, but should consider the totality of the evidence in the case, and assess the impact of any inconsistencies on questions of credibility and reliability pertaining to the core issue in the case.”

The Supreme Court noted the observations of Lord Hoffman in a British case, In re B (Children), [2008] 3 W.L.R. 1, [2008] UKHL 35:

“Common sense, not law, requires that in deciding this question, regard should be had, to whatever extent appropriate, to inherent probabilities.” 

The Canadian Court added,

“It will be for the trial judge to decide to what extent, if any, the circumstances suggest that an allegation is inherently improbable and where appropriate, that may be taken into account in the assessment of whether the evidence establishes that it is more likely than not that the event occurred.  However, there can be no rule of law imposing such a formula.”

To conduct a full, fair and balanced evidence an investigator must rely on this standard of proof when making a determination as to whether or not discrimination and/or harassment occurred. If you require assistance conducting an investigation, please contact us.