Collaery, 75, is fighting allegations he unlawfully shared classified information about a 2004 Australian spy operation that bugged the office of East Timor's prime minister during negotiations over oil and gas resources in the Timor Sea.

He was charged in 2018 with breaching the Intelligence Services Act and a directions hearing for his case on Thursday in the ACT Supreme Court was vacated.

An ABA council meeting this week unanimously expressed concerns about the delays in the prosecution and secret nature of proceedings.

"This matter raises two, fundamental rule of law questions as to the fair and open administration of justice - the length of time it has taken to prosecute the matter, and the suppression of evidence," ABA president Matthew Howard SC said in a statement.

"For the public to have confidence in the administration of justice, it is vital that prosecutions proceed in a timely manner, and that the workings of the courts be open to public scrutiny to the maximum extent possible."

The ABA's call for the attorney-general to review the prosecution follows one made by the ACT Bar Association in April when it said the government had spent $3 million pursuing Collaery.

The prosecution stems from his representation of Witness K, an Australian intelligence agent who blew the whistle on the bugging operation.

He was handed a three-month suspended prison sentence in June after pleading guilty to conspiring to reveal classified information.

Others who have criticised Collaery's prosecution include former East Timor president Jose Ramos-Horta, former Victorian premier Steve Bracks and independent federal MP Andrew Wilkie.

Collaery, a former ACT deputy chief minister, was awarded the Australian Lawyers Alliance's 2018 Civil Justice Award for his advocacy for Timor-Leste.

Australian Associated Press