Abstract
The High Court's tentative moves toward adopting structured proportionality as a method of constitutional review have been hampered by concerns about the separation of powers. This article argues that the manner in which a court undertakes proportionality analysis is crucial to the question of whether it is acting within the domain of judicial power. In this regard, the concept of judicial deference plays a vital but thus far under-theorised role. Deference refers not to judicial submission or surrender to the legislature, which would abdicate judicial power to a non-judicial body. Rather, it refers to a court giving weight to the judgment or opinion of government in circumstances of normative or empirical uncertainty. Courts afford deference in this way for two reasons: the desirability of respecting decisions made by democratically legitimate decision-makers, and the practical advantages that inhere in relying on the institutional competence and expertise of the other branches of government. An increased understanding of these rationales for deference in the context of constitutional review would diminish concerns about the High Court straying outside the domain of judicial power. Proportionality and deference exist in a symbiotic relationship and should be addressed together by a coherent judicial theory; many of the concerns raised by the High Court about the former would diminish were it also to embrace the latter.