The division of powers refers to the way the Constitution has allocated law-making powers to Commonwealth and/or state parliaments. The founders of the Constitution ensured that the powers of each parliament were clearly established in order to ensure that federation would succeed. There are four types of law-making powers. 

Specific powers

Specific powers are those clearly outlined in the written words of the constitution. For example, section 51(i) establishes that the Commonwealth has the power to make law with regard to trade and commerce.¹ Specific powers will also be either exclusive or concurrent powers.

Exclusive powers

Exclusive powers are law-making powers that solely belong to Commonwealth Parliament and therefore cannot be legislated on by the states. Law-making powers may be exclusive by their nature (i.e. by common sense, the area should be legislated on by the Commonwealth alone). An example of this is section 51(xix), which outlines that the Commonwealth has the power to legislate on ‘naturalisation and aliens’ (immigration).² Alternatively, law-making powers may be made exclusive by way of prohibitions being placed on the states. This means that the Constitution, in one section, gives a certain power to the Commonwealth, and, in another, prohibits the state from making law on that area. For instance, section 51(vi) gives the Commonwealth the power to make law on defence, and section 114 prohibits the states from raising armies or navies.

Concurrent powers

Concurrent law-making powers are those, which are specifically outlined in the Constitution, and, are shared between the Commonwealth and the states. For example, section 51(ii) states that the Commonwealth has the power to legislate on issues of taxation.³ However, this power is shared. The Commonwealth legislates and regulates income tax, whereas the states legislate and regulate land tax.

Section 109

Section 109 deals with the situation of conflicting laws made by the Commonwealth and the states. This section states that the Commonwealth law will always prevail, and the state law, to the extent of the inconsistency, will become invalid.⁴ For instance, as of 2004 the Marriage Act has explicitly stated that legal marriages can only take place between one man and one woman.⁵) Therefore, despite family law being a concurrent law-making power, states can not legislate to contravene this.

Residual powers

Residual law-making powers are not mentioned in the Constitution. Therefore, they solely belong to the states. Crime and education are examples of areas in which the states solely can legislate. This can lead to inconsistent laws between the states.

See also:

Constitution of Australia

Restrictions on the law-making powers of the state and Commonwealth parliaments

1. Commonwealth of Australia Constitution Act 1900 UK, http://www.aph.gov.au/About_Parliament/Senate/Powers_practice_n_procedures/Constitution . ↩

2. ibid. ↩

3. ibid. ↩

4. ibid. ↩

5. Marriage Amendment Act 2004 (Clth ↩