The Meaning of an Alien in the Constitutional Universe

This article considers the meaning of the word 'alien' in s51(19) of the Constitution. This is a very important power. It is increasingly the one relied upon by the Commonwealth to deport individuals. However, there has historically been uncertainty over the meaning of the word, with different approaches evident. The High Court has in the past permitted parliament to define the word to include individuals born in Australia, and for parliament to have broad latitude in defining the word. It is considered problematic to permit parliament to effectively define a word in the Constitution, given that that document is the source of parliament's power.