ABSTRACT
Detailed consideration of the royal prerogative will be undertaken in Chapter 6. The royal prerogative has significant implications for the separation of powers. Being the residue of monarchical power, the prerogative is part of the common law and thus amenable to the jurisdiction of the courts. Today, the vast majority of prerogative powers are exercised by the government in the name of the Crown. As will be seen later, the substance of many prerogative powers is political, entailing matters of policy which the judges are not competent to decide or – to phrase it differently – matters which, if ruled on by the judges in a manner inconsistent with the interpretation of the executive, would place the judges in a sensitive constitutional position and open to accusations of a violation of the separation of powers. That is not to suggest, however, that the courts have no role to play with respect to the royal prerogative. The traditional role of the courts is to rule on the existence and scope of the prerogative, but – having defined its existence and scope – to decline thereafter to rule on the exercise of the power. However, in Council of Civil Service Unions v Minister of State for Civil Service (1985) (the GCHQ case), the House of Lords made it clear that the courts have jurisdiction to review the exercise of executive power irrespective of whether the source of power is statutory or under the prerogative. Having seemingly extended the jurisdiction of the courts in relation to the prerogative, the House of Lords, nevertheless, proceeded to rule that there exists a wide range of ‘nonjusticiable’ matters which should be decided by the executive rather than the courts: a clear expression of the separation of powers.
