Section 51(xxix) of the Australian Constitution provides the Commonwealth Parliament with the power to make laws in relation to external affairs - VCE - SSCE Legal Studies - Question 4 - 2019 - Paper 1

The statement by Chief Justice Gibbs in the Koowarta case emphasizes the significant powers granted to the Commonwealth Parliament under section 51(xxix) of the Constitution, specifically regarding external affairs. This provision allows the Parliament to legislate in accordance with international agreements made by the executive branch.

Gibbs’ assertion implies that if the executive enters into any international agreement, the Parliament has the authority to enact laws that would operationalize these agreements domestically. This means that the legislative power is not limited in scope, as any international treaty or agreement could be transformed into domestic law by Parliament, reinforcing the notion of 'unlimited legislative power' in this context.

Further exemplification can be drawn from cases like the Tasmanian Dam case, where the Court recognized the Parliament's ability to legislate regarding international treaties, thereby supporting the argument that Parliament's legislative powers are expansive when it comes to foreign agreements and treaties.