The reason the man dubbed Witness J was charged and jailed in secret in Canberra may soon be made public.
Witness J spent 15 months in Canberra's jail after he pleaded guilty to mishandling classified information.
The precise charges have never been revealed, and his imprisonment only came to light when he unsuccessfully took legal action against the jail.
At the time, the case was able to be kept secret under Section 22 of the National Security Information Act (NSI), in what was an unprecedented case.
But today, Witness J's lawyer Joshua Nottle told the ACT Supreme Court it was time the judge's sentencing remarks in the original case were made public.
"The community is entirely in the dark about the facts and circumstances of the offence with which [Witness J] was charged, pleaded guilty to, was convicted of, and sentenced for," he said.
"The court should seek to provide as much information to the public as is consistent with the protection of legitimate national security concerns."
And Mr Nottle has found an ally for his cause in federal Attorney-General Mark Dreyfus, who has also accepted it is in the public interest for the material to be released, subject to some redactions to protect national security.
"We all agree as much as possible should be released," Angus Berger, counsel for the Attorney-General, said in court today.
Mr Berger told the court it had been provided with an open affidavit about the case and a closed one, which included a redacted version of the sentencing.
"The Attorney-General has advised the court which parts of the sentencing reasons continue to require protection under the NSI Act orders," Mr Berger said in his written submissions.
Mr Nottle said his client agreed with those terms.
"[Witness J] accepted during the sentencing proceedings … and continues to accept that there are legitimate national security concerns arising from parts of the transcript," Mr Nottle said.
Witness J's real name still likely to remain secret
Even if the judge's sentencing remarks are made public, they are likely to be redacted with several things remaining secret, including Witness J's real name.
Lawyers for the Commonwealth have also asked the court to place a long suppression on any redacted material.
"As explained in the confidential affidavit, the sensitivity of the 'national security information' in the sentencing decision is likely to endure for many years," Mr Berger said.
"Therefore, if the court is minded to revisit in the future whether further parts of the sentencing reasons can be published, this should not be for a considerable period of time."
Chief Justice Lucy McCallum will deliver her decision on whether the sentencing remarks and a summary explaining the ruling should be released next week.
