The Commonwealth Constitution sets out the responsibilities of the Commonwealth and State Governments. Included in the Constitution are lists of exclusive and concurrent powers [ss 51 and 52]. Where there is no specific mention in the Constitution of a particular power, then the matter is generally regarded as a State responsibility.

When the Constitution was drafted in the 1890s, the environment was not regarded as a particular issue of national importance. Accordingly, there is no specific mention of "conservation" or "the environment" in the list of Commonwealth powers. This means that matters such as air and water quality or resource exploitation are left for the States to regulate.

Whilst the States may have primary responsibility for the environment, the Commonwealth still has significant powers which can be used to make laws about the environment. For example, the Commonwealth has responsibility for foreign affairs and international treaties and this can be used to pass laws to give effect to international treaties Australia has signed (such as the World Heritage Convention). More recently, Australia's obligations pursuant to the Paris Agreement (2015) enabled the commencement of the Climate Change Act 2022 (Cth) on 14 September 2022. The Climate Change Act 2022 (Cth) sets targets to reduce Australia's net greenhouse gas emissions as follows:

In some areas, Commonwealth and State powers and operations overlap, resulting in both State and Commonwealth legislation on the same subject matter. In the event of such a conflict, the Commonwealth laws prevail. Increasingly, Commonwealth and State governments are trying to co-operate to avoid duplication in environmental assessment or regulation. For example, where both State and Commonwealth legislation require an Environmental Impact Statement, then a single process would normally be followed to satisfy both sets of laws.

Under the Constitution, the Commonwealth is directly responsible for Commonwealth land, the management of Australia's external territories and the coastal seas outside the State three-mile limit, (but within the 200km "exclusive economic zone").

Commonwealth laws are administered by a number of regulatory authorities. In most cases the Department of Climate Change, Energy, the Environment and Water is the relevant authority.

To find out which particular part of the Department of Climate Change, Energy, the Environment and Water is responsible for administering Commonwealth environmental law, telephone the Department on free call 1800 803 772 or visit the Department of Climate Change, Energy, the Environment and Water.

The main Commonwealth legislation dealing with the environment is the Environment Protection and Biodiversity Conservation Act 1999 (Cth). This Act is covered in a separate part of this chapter.