Australia's common law was inherited from the United Kingdom. And that in turn developed from the Magna Carta of 1215 - probably the first human rights treaty in the western world - between King John and his Barons. So human rights regulating the freedom of the citizen and limiting the power of the King or government are fundamental to our law.
Common law is often called 'judge-made' law. This distinguishes it from laws made in Parliament. It is certainly true that many protections we can identify as human rights are protected by Australian judges applying common law principles.
Examples include the obligation of a court to refuse to allow an unfair trial to go ahead (even though the common law does not recognise a right to free legal representation in a criminal trial) [i] and the interpretation of permissible limits on freedom of movement within Australia. [ii]
Common law can be expanded or reduced by legislation passed by Parliament. This frequently happens. An example of reduction is the common law principle that the police have no power to detain someone for questioning. [iii] South Australia's Summary Offences Act 1953 grants the police this power where a serious offence is suspected. [iv] An example of expansion is the recognition in legislation of the equality of men and women. Judges developing common law principles refused to make this recognition, instead treating their sex as a disability for women, disentitling them from pursuing many professions.
See Common law defences for further information.
[i] Dietrich v R ( 1992) 177 CLR 292
[ii] The test for the lawfulness of restrictions on freedom of interstate commerce (as guaranteed by the Constitution) was stated in various ways in Cunliffe v The Commonwealth (1994) 182 CLR 272
[iii] R v Lemsatef  2 All ER 835, per Lawton LJ at page 839
[iv] Section 78 inserted in 1985. From Human Rights and Equal Opportunity Commission