Judicial independence is regarded as one of the foundation values of the Australian legal system, such that the High Court held in 2004 that a court capable of exercising federal judicial power must be, and must appear to be, an independent and impartial tribunal. Former Chief Justice Gerard Brennan described judicial independence as existing "to serve and protect not the governors but the governed", albeit one that "rests on the calibre and the character of the judges themselves". Despite general agreement as to its importance and common acceptance of some elements, there is no agreement as to each of the elements of judicial independence.
Aspects of judicial independence can be seen as complementary, such as appeals serving to ensure that decisions are made on the facts and law, but which also serves to enhance public confidence in the judiciary. This however is not always the case as there are other elements that require balance, for example public confidence in the judiciary necessarily impacts on security of tenure in that it requires the ability to remove judges who are unfit for office. Similarly there may be tension between tenure of existing judges and the appointment of the best available candidate to a judicial position. The principle of judicial independence was not always observed in colonial Australia.
Impartial
The underlying principle is that a judge is an impartial decision maker, whether the parties are individuals, government or other corporate bodies, such that it is the "judge sitting on a case, who has heard the evidence and arguments, who makes the decision on the basis of an application of the law to the evidence and arguments presented". This carries with it the requirement that the judge is free from improper influences, whether from the parliament, executive or other powerful interest groups such as the media. The need for impartiality is reflected in the judicial oath “to do right to all manner of people, according to law, without fear or favour, affection or ill will”. The need for public confidence in the impartiality of the judiciary, that "justice must be done and be seen to be done", gives rise to the rule disqualifying a judge where "a fair-minded lay observer might reasonably apprehend that the judge might not bring an impartial and unprejudiced mind to the resolution of the question the judge is required to decide".
Initial principles
The independence of the English judiciary is traditionally said to have been established by the Act of Settlement 1701 which made relevantly two provisions, that a judge's salary was required to be fixed on appointment and that the judge could only be removed by the crown on upon the address of both Houses of Parliament. These provisions did not apply to colonial judges, covered by the Colonial Leave of Absence Act 1782 (22 Geo. 3. c. 75 (Imp)), known as Burke's Act, which provided a judge could be removed by the governor and council of the colony, subject to the right of appeal to the Privy Council.
Immunity from suit
The common law of England has long held that a judge had immunity from being sued for any act within jurisdiction, even if the judge acted maliciously or corruptly. The courts have denied that rule exists for the protection of the malicious or corrupt judge, and justified it on the grounds of the public interest in the independence of the judiciary as being necessary for the administration of justice. The history of development of this immunity is complex, and the High Court held in 2006 that it is "ultimately, although not solely, founded in considerations of the finality of judgments".
Security of tenure
Security of tenure, leaving a judge free from influence resulting from the threat of removal, is generally said to be justified as an important feature of judicial independence. In the 1891 constitutional convention the protection required an address passed by the relevant houses of parliament. In Adelaide in 1897 the power to remove was limited to cases of "misbehaviour or incapacity", while in 1898 in Melbourne the convention added the requirement for proof, which Quick and Garran writing in 1901, said was to ensure that the judge should be heard in defence and that the charge had to be alleged in the address. In 1918 the High Court held that tenure must be for life to that particular court, not merely for a term of years.