[1] It is an interpretive presumption by the judiciary that Australia's various parliaments do not intend to curtail or abrogate fundamental rights and freedoms when enacting legislation.
It has been said that the doctrine as it is understood and articulated in its modern form 'has transformed a loose collection of rebuttable interpretive presumptions into a quasi-constitutional common law bill of rights'.
[2] Other jurisdictions, including the UK and New Zealand, also apply the principle of legality doctrine; albeit with its application and reasoning differing according to their respective jurisprudence.
Over centuries, jurisprudence emerged as a means to reconcile the principles of parliamentary sovereignty, and those of established common law rights.
Throughout the 20th century and beyond, the Australian High Court articulated these principles when interpreting statutes, including notably in the decisions Coco v The Queen, and Electrolux v AWU.
General words will rarely be sufficient for that purpose if they do not specifically deal with the question because, in the context in which they appear, they will often be ambiguous on the aspect of interference with fundamental rights - Mason CJ, Brennan, Gaudron and McHugh JJ, at paragraph 10Chief Justice Gleeson's statement of the doctrine in Electrolux has been repeatedly endorsed by the courts.
[2] This may be contrasted with its past articulations, like that found in Potter v Minahan (1908), which instead tended to rely on judicial incredulousness at parliament's intentions; as the normative justification for reading down statutes.
The principle of legality plays an important role in providing a balance between parliamentary sovereignty and the protection of individual rights.
By encouraging a rights-conscious approach to legislative interpretation, the principle of legality contributes to the protection and promotion of human rights in Australia.