Redlich and Nettle JJA [at 106]:
The Commission contended that, when a trial judge determines to grant or refuse an adjournment of the trial, the judge acts in an administrative capacity within the meaning of s 4(1) of the Charter and thus as a public authority within the meaning of s 38(1) of the Charter. It followed, it was contended, that the courses of action open to the judge are limited to those which are demonstrably justifiable having regard to the criteria delineated in s 7(2) of the Charter.
The Commission’s contention is quite unsustainable. The function to grant or refuse an adjournment is one which takes its character from the tribunal or court in which the function is reposed. Where, therefore, the power to grant or refuse an adjournment of a trial is reposed in a trial judge, it is to be inferred that it is to be exercised judicially and thus that the character of the function is judicial. More precisely, when a trial judge determines to grant or refuse an adjournment of the trial, the judge exercises judicial power which involves the governance of a trial for the determination of criminal guilt and its punishment or, in a civil proceeding, the determination of a dispute inter partes. That is not an administrative function.
Sabet v Medical Practitioners Board of Victoria or Kracke v Mental Health Review Board, on which the Commission relied, were concerned with administrative tribunals. Plainly, they involve different considerations. It should not be thought that anything said in either case was supportive of the Commission’s position.
Section 331 of the Criminal Procedure Act 2009 confers a wide discretion on judges and magistrates to grant or refuse adjournment applications in criminal matters.
It's not clear yet to what extent the High Court's decision in Aon Risk Services v Australian National University (2009) 258 ALR 14 should influence the exercise of that discretion. Instinctively I would have thought not much, but the Judicial College's case note on the Aon decision suggests otherwise:
While this decision primarily affects the civil jurisdiction and relies heavily on the ACT Court Rules, it is arguably relevant in all cases when a party seeks an indulgence from the court without adequate justification or when granting the application will prejudice other court users by delaying the resolution of cases.
In this state, of course, concerns about court efficiency must be read in light of Charter rights like ss 24 and 25.
The common law position is that an application for the adjournment of a trial should be based on evidence, unless the facts are manifest or admitted: R v Jones  VR 72. Nettle, Harper and Hansen JJA in AJP v R  VSCA 224 [at 17]:
Mere assertions of the Bar table leave a judge without the means to properly assess the merits of an application and are likely to result in its rejection.
Applications for adjournment are interlocutory in nature and the rules of evidence do apply: s 4 Evidence Act. (Though some of the Act may be waived by agreement of the parties under s 190 if the accused is represented).
A number of recent interstate decisions have reinstated charges dismissed due to the prosecution's failure to be ready for hearing. Elucubrator blogged in May about Police v Beard  SASC 49, a case where the SA Supreme Court overturned a magistrate's order striking out the charge because of the prosecution's failure to meet its disclosure obligations. DPP (NSW) v Maleselo Fungavaka & Anor  NSWSC 917 is a similar case.
In Lusted v Menichelli  TASSC 15 the police had failed to arrange for the attendance of a witness serving sentence at Risdon Prison. The charges were struck out, but that decision was set aside by the Tasmanian Supreme Court and the charges remitted for hearing.
In Police v Vuckic  SASC 271, the prosecution had failed to call an important witness, and the decision to refuse the adjournment and strike out the charge was considered invalid. Interestingly, Duggan J quoted Sali v SPC Ltd & Anor (1993) 116 ALR 625, where Brennan, Deane and McHugh JJ [at 628] had said,
An adjournment which, if refused, would result in a serious injustice to the applicant should only be refused if that is the only way that justice can be done to another party in the action.
This was exactly the sentiment disapproved in Aon. It seems the notion that costs are sufficient compensation to prejudice remains alive and well.