Abstract
This article explores the idea of Parliamentary sovereignty in British constitutional theory. Two general explanations for this idea are considered: firstly, that the existence of a sovereign entity is a conceptually necessary precondition for the existence of a state or constitution; secondly, that Parliament is sovereign, if it is, in virtue of a rule of recognition whose existence and content may be empirically determined. The former account, it is suggested, looms large in orthodox British constitutional theory but cannot be sustained. Herbert Hart's version of the latter account is examined by reference to the decision in Jackson v Attorney General but is also found wanting. Given the inadequacy of these accounts, it is contended that the idea of Parliamentary sovereignty is misconceived. Building on insights in the work of Hart and Dworkin, it is argued that the British constitution instead rests on the ideal of government under law or the principle of legality. The putative value of legality, it is contended, will shape or control the many different principles that condition the exercise of official power