chapter  6
11 Pages

Parliamentary sovereignty, constitutional dialogues and sunset clauses

Besides separation of powers, parliamentary sovereignty is also a cornerstone of the UK constitution. The sovereignty of Parliament, or in other words the supremacy of Parliament (as it is also described), 1 is a doctrine well-respected in the UK, as all constitutional and political theorists agree. 2 Although these two doctrines are distinct from each other, their interaction is inevitable. Masterman asserts that ‘the role and powers of Parliament are key to any understanding of the UK constitution, and therefore, to any understanding of the separation of power with the constitution’. 3

Dicey crystallised the concept of parliamentary sovereignty, famously saying that:

Parliament thus defi ned has, under the English constitution, the right to make or unmake any law whatever; and, further, that no person or body is recognised by the law of England as having the right to override or set aside the legislation of Parliament. 4

The defi nition by Dicey provides us with the two elements of the doctrine; the positive aspect that Parliament – to be more precise, the Queen in Parliament – can legislate on whatever subject without limits, and the negative aspect that no court can set aside its legislation. 5

Thus according to the above, on the one hand no Parliament can entrench legislation and, consequently, future Parliaments are equally autonomous to amend any law in an

other words, parliamentary sovereignty does not permit past and present Parliaments to impose constraints on future Parliaments, and it limits the space for interaction between the legislature and the judiciary. 7

But the doctrine of parliamentary sovereignty has suffered a series of incursions. Relevant to the possibility to have laws entrenched are the following: one of the fi rst limitations may have been realised after the entry of the UK into the European Union, in the Factortame litigation. 8 Subsequently the adoption of the Human Rights Act in 1998 had great infl uence, given that this act created another exception to the doctrine of implied repeal, 9 as did the Supreme Court’s decision in the HS2 case, 10 more recently, according to which a number of statutes with constitutional value are not subject to the doctrine of implied repeal. 11

Moreover, the adoption of the Human Rights Act has equally affected the negative aspect of the doctrine of parliamentary sovereignty. Although courts cannot strike down an act of Parliament, they can declare it incompatible with the European Convention of Human Rights. 12 Tomkins admits that the incorporation of the European Convention of Human Rights into the law of the UK contributed to the strengthening of the judges’ role, 13 and Lord Hope, in his 2005 decision in Jackson v Attorney General , remarked that ‘our constitution is dominated by the sovereignty of Parliament. But Parliamentary sovereignty is no longer, if it ever was, absolute’. 14

The weakening of the doctrine of parliamentary sovereignty has opened up room in the constitutional order for new constitutional phenomena, in particular that of constitutional dialogue between the courts and Parliament. In principle, this dialogue depends mainly on

permits a degree of interaction between the institutions.