16.1 Under the constitutional doctrine of the separation of powers, parliaments make laws, the executive administers or enforces laws, and the judiciary adjudicates disputes about the law. The doctrine is reflected in the structure of the Australian Constitution: Chapter I is entitled ‘The Parliament’; Chapter II, ‘The Executive Government; and Chapter III, ‘The Judicature’. But these powers are not as separate and the distinctions not as clear as some might imagine. For one thing, in Australia, members of the executive (the Cabinet and other government ministers) are also members of the legislature.
16.2 Nevertheless, from the separation of powers doctrine may be derived the principle that legislative power should not be inappropriately delegated to the executive. Although it is common for Parliament to delegate the power to make laws to the executive—not only to government ministers, but also government agencies such as the Australian Taxation Office and the Australian Securities and Investments Commission—this chapter is about when this would not be appropriate.
16.3 This chapter is concerned with laws that delegate legislative power, rather than with laws that give ministers and government agencies executive power. There may be no bright line between legislative and executive power, but the distinction is ‘essentially between the creation or formulation of new rules of law having general application and the application of those general rules to particular cases’. Creating new rules of law of general application is traditionally the role of Parliament.