Landmark decision reforming the framework for judicial review of administrative decisions.
The Court established a presumption that reasonableness is the applicable standard of review, rebuttable where the legislature has indicated a different standard (including by providing a statutory appeal mechanism) or where the rule of law requires correctness review on constitutional questions, general questions of central legal importance, or jurisdictional boundaries between administrative bodies.
The Court also provided extensive guidance on conducting reasonableness review.
On the merits, the Registrar's decision to cancel the respondent's citizenship certificate was found unreasonable, as the statutory exception denying citizenship by birth to children of foreign government employees was intended to apply only to individuals whose parents had been granted diplomatic privileges and immunities.
