Thanks for the complex question Trudy! When the Australian Constitution came into effect of 1 January 1901, the power of the states to make laws was broken up so that some powers were:
Areas in which only the Commonwealth can make laws are called exclusive powers. Section 51 of the Constitution contains a long list of areas in which the Commonwealth can make laws. For some of these – defence, foreign affairs, overseas trade etc – the Commonwealth has the exclusive (sole) power to make laws. Others – education, health etc – are shared with the states. Sections 52, 86 and 90 (customs), and 122 (territories) also contain exclusive powers of the Commonwealth.
Concurrent powers refers to areas in which both the Commonwealth and states can make laws. Section 109 of the Constitution syas that where a state law conflicts with a federal law, the state law is cancelled.
Any area not covered in the Constitution is considered to be within the states’ powers to make laws and is called a residual power. These are the powers that were not transferred to the Commonwealth at federation. Residual powers include urban planning and civil law.
For more information on what the Commonwealth and the states can make laws about, check out the three levels of government.