The Royal Prerogative

This briefing paper sets out the constitutional basis to the Royal Prerogative, describes general prerogative powers and the Crown's personal prerogative powers. It then sets out recent proposals for reform, and the case law that has led to the current understanding of the prerogative.

The Royal Prerogative is one of the most significant elements of the UK’s constitution. The concept of prerogative powers stems from the medieval King acting as head of the kingdom, but it is by no means a medieval device. The prerogative enables Ministers, among many other things, to deploy the armed forces, make and unmake international treaties and to grant honours. In modern times, Government Ministers exercise the majority of the prerogative powers either in their own right or through the advice they provide to the Queen which she is bound constitutionally to follow.

Three fundamental principles of the prerogative are:

• The supremacy of statute law. Where there is a conflict between the prerogative and statute, statute prevails. Statute law cannot be altered by use of the prerogative;
• Use of the prerogative remains subject to the common law duties of fairness and reason. It is therefore possible to challenge use of the prerogative by judicial review in most cases;
• While the prerogative can be abolished or abrogated by statute, it can never be broadened. However, Parliament could create powers by statute that are similar to prerogative powers in their nature.

Court rulings have restricted the circumstances in which prerogative powers can be used, determined when prerogative powers are subject to judicial review, and established how statute law interacts with prerogative powers.

The intended use of prerogative powers to activate Article 50 of the Treaty of the European Union was recently challenged in the Supreme Court, in R. (on the application of Miller) v Secretary of State for Exiting the European Union.

There have been calls to reform prerogative powers, chiefly because they are exercised without any parliamentary authority. In the 2001 and 2005 Parliaments, the Public Administration Select Committee, repeatedly examined the prerogative, calling for its reform. The 2007 government of Gordon Brown also examined prerogative powers, producing draft legislation and an important green paper on the governance of Britain. Calls for reform of the prerogative have subsided somewhat in recent years, though there have been prominent reforms. The Constitutional Reform and Governance Act 2010 put the regulation of the civil service on a statutory basis, and introduced a statutory role for Parliament in treaty ratification. In addition, the Fixed-term Parliaments Act 2011 abolished the former prerogative power to dissolve Parliament. These moves that put prerogative powers on a statutory footing are usually considered to permanently abridge prerogative power.