Bernard Collaery has pushed back against continued efforts to keep a key judgement in his case secret, with one of the whistleblower's barristers describing them as "pointless" and "a waste of court time".
But counsel for the federal Attorney-General insists publishing the document without further redaction would not be "in the interests of national security" because classified information would be disclosed.
Nearly three months after the nation's chief law officer, Mark Dreyfus KC, took the unprecedented step of discontinuing the case against Mr Collaery, the latter was back in the ACT Court of Appeal on Friday.
Mr Collaery, a Canberra lawyer, had been due to stand trial in October, charged with four counts of breaching the Intelligence Services Act by unlawfully communicating classified information to journalists.
He was also accused of conspiring with a former client, the ex-Australian Secret Intelligence Service spy known as Witness K, to share such information with the government of East Timor.
The information related to a 2004 espionage operation, in which Australian spies bugged a government building in East Timor during negotiations to carve up lucrative oil and gas reserves.
While Mr Dreyfus exercised powers under the Judiciary Act to terminate the prosecution of Mr Collaery in July, the Labor Attorney-General has adopted the attitude of his Liberal predecessor, Michaelia Cash, in relation to the public release of a key judgement delivered last October.
That document outlines why the court upheld an appeal by Mr Collaery and overturned a ruling of Justice David Mossop, who had decided large parts of the 77-year-old's trial would be held behind closed doors to prevent the disclosure of certain information likely to prejudice national security.
The court, constituted at the time by former chief justice Helen Murrell, Justice John Burns and Justice Michael Wigney, released a one-page judgement summary that said there was a risk the public disclosure of that information would prejudice national security.
But the trio doubted whether that risk would materialise, and said the greater problem lay in the fact public confidence in the administration of justice would be jeopardised by a largely secret trial.
"The court emphasised that the open hearing of criminal trials was important because it deterred political prosecutions, allowed the public to scrutinise the actions of prosecutors, and permitted the public to properly assess the conduct of the accused person," part of the summary said.
The full judgement has never seen the light of day because Senator Cash, unhappy with the amount of redaction Chief Justice Murrell proposed to apply to it, sought special leave to appeal to the High Court for greater secrecy.
While the High Court application was later withdrawn, Perry Herzfeld SC, a barrister for Mr Dreyfus, argued on Friday that new ACT Chief Justice Lucy McCallum should revisit the issue in the Court of Appeal.
Mr Herzfeld said circumstances had changed since last October, in part because the prosecution of Mr Collaery had been discontinued.
"Publication of the judgement without the redactions we seek will tend to disclose material in the prosecution brief that is protected from disclosure," he said.
But Phillip Boulten SC, acting for Mr Collaery, argued the question of redaction was "not a matter that should be reventilated".
To look at it again was, Mr Boulten argued, "as good as a pointless exercise" and "a waste of court time".
Mr Boulten added that Mr Herzfeld had not put forward any argument that Chief Justice Murrell had erred, saying the Attorney-General simply did not like her decision.
Further arguments were held in closed court on Friday afternoon, when Chief Justice McCallum ultimately reserved her decision.
Kieran Pender, a senior lawyer with the Human Rights Law Centre, called on Mr Dreyfus to end what he called an "absurd pursuit of secrecy".
"The Attorney-General has bigger priorities than continuing the secrecy obsession of the former government," Mr Pender told The Canberra Times.
"Dropping the ongoing whistleblower prosecutions, of Richard Boyle and David McBride, reforming our broken whistleblowing laws and establishing a whistleblower protections authority should all be on his to-do list, not this latest attempt to erode open justice."
