What is the test for disqualifying a judge on the basis of bias?

First, as a matter of law, there is a strong presumption of judicial impartiality, which is not easily displaced. Second, there is a heavy burden of proof upon the person making the allegation to present cogent evidence establishing “serious grounds” sufficient to justify a finding that the decision-maker should be disqualified on account of bias. Third, whether a reasonable apprehension of bias exists is “highly fact-specific”. Such an inquiry is one where the context, and the particular circumstances, are of supreme importance. The allegation can only be addressed carefully in light of the entire context. There are no shortcuts. See Wewaykum Indian Band v. Canada, 2003 SCC 45.