Appeal-Judicial Review - Fairness and the Common Law Brown v. Canada (Citizenship and Immigration)
In Brown v. Canada (Citizenship and Immigration) (Fed CA, 2020) the Federal Court of Appeal comments on administrative procedural fairness as a form of the common law, here in the immigration detention context:
 Where a decision affects the rights, privileges or interests of an individual, the common law duty of fairness is triggered (see, e.g., Cardinal v. Director of Kent Institution, 1985 CanLII 23 (SCC),  2 S.C.R. 643, 24 D.L.R. (4th) 44 at 653; Baker at para. 20). The greater the effect a decision has on the life of an individual, the more robust will be the procedural protections required to fulfill the duty of fairness and the requirements of fundamental justice under section 7 of the Charter (Charkaoui at para. 25, quoting Suresh v. Canada (Minister of Citizenship & Immigration), 2002 SCC 1,  1 S.C.R. 3 at para. 118). At a minimum, the duty of fairness requires that the affected person know the case they have to meet and have an adequate opportunity to respond. The procedural rights afforded under section 7 of the Charter provide the same protection for detainees (Charkaoui at paras. 28-29, 53).. Green v Law Society of Manitoba
In Green v. Law Society of Manitoba (SCC, 2017) the Supreme Court clarifies that the common law administrative duty of fairness exists independent from any delegated rule regime, and can operate to supplement such regimes (eg. to require a hearing where the regime does not expressly do so):
 The common law duty of procedural fairness does not reside in a set of enacted rules. As Brown and Evans explain, “delegated legislation that apparently permits a fundamental breach of the duty of fairness will not normally be found to be exhaustive of procedural rights”: Judicial Review of Administrative Action in Canada (loose-leaf), at topic 7:1512. A statutory decision-maker can always provide for procedures in addition to those set out in a rule in order to ensure that the dictates of procedural fairness are met: see Culligan v. Miller, J. (1996), 1996 CanLII 11286 (NB QB), 178 N.B.R. (2d) 321 (Q.B.), at paras. 23-24; Shewchuk-Dann v. Assn. of Social Workers (Alberta) (1996), 38 Admin. L.R. (2d) 19 (C.A.); Laferrière v. Canada (Attorney General), 2015 FC 612, at paras. 13-14 (CanLII); Irwin v. Alberta Veterinary Medical Association, 2015 ABCA 396 (CanLII), 609 A.R. 299, at paras. 58 and 63. However, the common law duty of fairness “supplements existing statutory duties and fills the gap” where procedures are not provided for explicitly: G. Huscroft, “From Natural Justice to Fairness: Thresholds, Content, and the Role of Judicial Review” in C. M. Flood and L. Sossin, eds., Administrative Law in Context (2nd ed. 2013) 147, at p. 152.