Bias Should be Raised Promptly. Speck v. OLRB
In Speck v. OLRB (Div Ct, 2021) the Divisional Court considered a judicial review of an OLRB duty of fair representation case. One of the issues was an allegation of bias:
 Bias is a component of procedural fairness and concerns the right to have a decision by an unbiased decision-maker. The test in respect of an administrative decision is: “what would an informed person, viewing the matter realistically and practically – and having thought the matter through – conclude. Would he think that it is more likely than not that [the decision-maker], whether consciously or unconsciously, would not decide fairly?”: Committee for Justice and Liberty et al. v. Canada (National Energy Board) et al., 1976 CanLII 2 (SCC),  1 S.C.R 369, at p. 394; Baker, at paras. 45-48.. Beddows v. Canada (Attorney General)
 A party is generally not permitted to raise allegations of bias on judicial review when they have not been properly raised before the tribunal of whose decision review is sought: Alberta (Information and Privacy Commissioner) v. Alberta Teachers’ Association, 2011 SCC 61,  3 S.C.R. 654, at para. 23. We do not consider the issue to have been properly placed before the Board either in submissions before the member that was considering the delay argument or in any request for reconsideration.
 .... As has been observed in our court, unsupported allegations of bias must be carefully controlled lest they become a tool for improperly seeking to overturn unfavourable decisions: Bart v. McMaster University, 2016 ONSC 5747 (Div. Ct.), at paras. 156-163.
 Further, in cases such as this, a presumption of impartiality applies to decision-makers on boards such as the OLRB, just as it would with respect to judicial decision-makers: Terceira v. Labourers International Union of North America, 2014 ONCA 839, 122 O.R. (3d) 521, at paras. 29-30. No evidence before us suggests any material pecuniary interest in this case by any members of the Board who dealt with this case that might ground even a reasonable apprehension of bias.
In Beddows v. Canada (Attorney General) (Fed CA, 2020) the Federal Court of Appeal noted the bias issues must be raised promptly by a party, not saved up until useful on appeal or judicial review:
 One of the appellant’s allegations – that of the alleged bias flowing from the role of the current CDS in the 2014 Grievance and as instructing authority – must be dismissed at the outset as the appellant raised this issue for the first time before this Court. It is well settled that allegations of bias are serious allegations that must be raised at the earliest possible opportunity (Canada (Human Rights Commission) v. Taylor, 1990 CanLII 26 (SCC),  3 S.C.R. 892, 117 N.R. 191). In International Relief Fund for the Afflicted and Needy (Canada) v. Canada (National Revenue), 2013 FCA 178, 449 N.R. 95 at para. 19, Justice Stratas of this Court cautioned that "“[o]ne cannot discover facts that might indicate impermissible bias on the part of the administrative decision-maker, remain silent on the matter of bias, await the outcome of the administrative decision, and then, if the decision is adverse, claim on appeal that the decision-maker was biased.”" Thus, the appellant’s bias arguments cannot be entertained.. Health Genetic Centre Corp. (Health Genetic Center) v. New Scientist Magazine
In Health Genetic Centre Corp. (Health Genetic Center) v. New Scientist Magazine (Ont CA, 2019) the Court of Appeal commented as follows on an allegation of bias:
 The appellants recognize that they bear the onus of establishing that an informed person viewing the matter realistically and practically – and having thought the matter through – would conclude that it was more likely than not that the trial judge, whether consciously or unconsciously, would not decide fairly: Stuart Budd & Sons Limited v. IFS Vehicle Distributors ULC, 2016 ONCA 60 (CanLII), 129 O.R. (3d) 37, at para. 47.
 The appellants also recognize that their burden is a heavy one, as the strong presumption of judicial impartiality is not easily displaced: Stuart Budd, at para. 48.
 We raise one additional principle. An apprehension of bias should be raised as soon as it is reasonably possible to do so: R. v. Curragh Inc., 1997 CanLII 381 (SCC),  1 S.C.R. 537, at para. 11. This principle protects the integrity of the court’s authority: Curragh Inc., at para. 11. It also ensures a full record, and prevents counsel from keeping allegations of bias in reserve and deploying them tactically upon receipt of an unfavourable decision. Furthermore, as Donald J.A. of the Court of Appeal for British Columbia has observed, “the genuineness of the apprehension becomes suspect when it is not acted on right away”: Eckervogt v. British Columbia, 2004 BCCA 398 (CanLII), 30 B.C.L.R. (4th) 291, at para. 48.