This will clarify why constitutional conventions are unwritten source of the UK’s constitution and whether they still remain significant today.
We do not have a single authoritative document identifying the principle institutions of the state and the powers held by each; and even where a system has a constitution in this sense; it never offers a complete description of that systems constitutional law. It is not correct, however, to say that the British constitution is “unwritten”. Our constitution is the aggregate of several sources, some written, some not; some legal in character, others non-legal in the sense of not being judicially enforceable or of deriving rather from the realms of legal and political theory 1
Constitution is based on conventions and that in turn those conventions are rules which play a vital role in the constitution although they are not enforced by rules of law. For Dicey, the central significance of constitutional conventions was that they prescribed the manner in which the prerogatives of power the crown (or of ministers or servants of the crown) fell to be excercised.2
Constitutional conventions hold no legal authority and can also be changed. Conventions are always emerging, crystallising and dissolving, and it is sometimes questionable whether a convention has been broken or has simply been changed 3 Constitutional conventions are far from permanent. This is due to the fact it is not created and bound by law. The conventions do not require formal repeal as citizens can simply avoid observing them. As time goes on the constitutional conventions will change along with it too. Dicey had identified two types of constitutional rule.
The one set of rules are in the strictest sense “laws”, since they are rules (whether derived from statue or… the common law) enforced by the courts. The other set of rules consists of conventions, understandings, habits or practises which, though they may regulate the conduct of…officials, are not in reality laws at all since they are not enforced by the courts”4 If there happened to be a disagreement between a convention and the legal rule, the court will always uphold the legal rule. Dicey distinguishes laws from conventions based on whether they can be imposed by the courts not on the level of their status.