In several sections of the Constitution the Governor-General’s powers and role are expressed. Section 2 provides that

A Governor-General appointed by the Queen shall be Her Majesty’s representative in the Commonwealth, and shall have and may exercise in the Commonwealth during the Queen’s pleasure, but subject to this Constitution, such powers and functions of the Queen as Her Majesty may be pleased to assign to him.

(…)

However, there are some powers which the Governor-General may, in certain circumstances, exercise without – or contrary to – ministerial advice. These are known as the reserve powers. While the reserve powers are not codified as such, they are generally agreed to at least include:

1. The power to appoint a Prime Minister if an election has resulted in a ‘hung parliament’;
2. The power to dismiss a Prime Minister where he or she has lost the confidence of the Parliament;
3. The power to dismiss a Prime Minister or Minister when he or she is acting unlawfully; and
4. The power to refuse to dissolve the House of Representatives despite a request from the Prime Minister.