Functus officio

Functus officio, an officer or agency whose mandate has expired either because of the arrival of an expiry date or because an agency has accomplished the purpose for which it was created. When used in relation to a court, it may also mean whose duty or authority has come to an end. "Once a court has passed a valid sentence after a lawful hearing, it is functus officio and cannot reopen the case."

Functus officio is thus bound up with the doctrine of res judicata which prevents the re-opening of a matter before the same court, tribunal or other statutory actor which rendered the final decision in the absence of statutory authority. There are many exceptions. For instance, where a statute authorizes variations of the original decision, the decision maker may revisit his or her previous decision. Common examples include competency hearings, parole board hearings and family law proceedings. However, there is an important difference between "res judicata" and "functus officio". "Res judicata" refers to the end of a case; "functus officio" refers to the expiration of an office. "Functus officio" derives from "fungere": to perform, end, expire. It is cognate to the ordinary English word "defunct". "Res judicata" means "the thing has been decided". "Res judicata" derives from the principle "interest reipublicae ut sit finis litium" (it is for the good of the commonwealth that there be a terminus to litigation).

Canadian doctrinal and judicial writing on functus officio is sparse, even though the rule itself derives from an old case of the English Court of Appeal (In re St. Nazaire Co. (1879), 12 Ch. D. 88). Essentially, the rule is that the court has no jurisdiction to reopen or amend a final decision, except in two cases: (1) where there has been a slip in drawing up the judgment, or (2) where there has been error in expressing the manifest intention of the court. More recently, this Court affirmed that this rule need not always be rigidly applied to tribunals in the administrative law context when the policy reasons for it are not present, In the Canadian case of Chandler v Alberta Association of Architects, Sopinka J. wrote in relation to the principle of functus officio: "The general rule (is) that a final decision of a court cannot be reopened .... The rule applied only after the formal judgment had been drawn up, issued and entered, and was subject to two exceptions: where there had been a slip in drawing it up, and where there was an error in expressing the manifest intention of the court."

The existence and scope of a right of appeal has often been made the focus of analytical attention in applying the functus doctrine. Such was the case when the power of the Court of Chancery to rehear cases was extinguished by the Judicature Acts in 1873 by fusing common law and equity jurisdictions into one court and providing for a single appeal to a newly created Court of Appeal (In re St. Nazaire, supra). Originally, this was also the focus of the functus analysis for administrative tribunals that had rights of appeal tightly constrained by statute (see Grillas v. Minister of Manpower and Immigration, 1971 CanLII 3 (S.C.C.), [1972] S.C.R. 577). However, the underlying rationale for the doctrine is clearly more fundamental: that for the due and proper administration of justice, there must be finality to a proceeding to ensure procedural fairness and the integrity of the judicial system. The point is plainly made by Sopinka J.

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Wikipedia