Former police officer Roger Rogerson who is behind bars in NSW for murder will be called to give evidence in the inquest into Brisbane's fatal 1973 Whiskey Au Go Go firebombing.
Rogerson is the only person still alive who signed a confession made days after the firebombing by James Richard Finch, one of two men convicted over the attack.
Coroner Terry Ryan said on Friday said he would call Rogerson to give evidence at the inquest.
Mr Ryan said he had considered the submission from Vincent O'Dempsey's lawyer Chris Minnery that Rogerson may be able to give direct evidence about events on March 11, 1973 when Finch was interviewed days after the attack.
"He was also present at the watch-house when charges were laid against Mr Stuart and Mr Finch so he could give direct evidence in relation to that," Mr Ryan added.
The inquest has been told Rogerson was brought into the investigation because of his understanding of possible connections with Sydney-based criminals.
"I am satisfied having regard to the matters that are relevant to this inquest and the evidence Mr Rogerson can possibly give that it is in the interests of justice ... for him to be produced," Mr Ryan said.
But he said there was a process that enabled Rogerson to apply to have the order set aside.
Counsel assisting Stephen Keim said earlier Rogerson's lawyer had instructed that his client would not consent to giving remote evidence.
The Whiskey inquest was reopened after the firebombing was mentioned in trials in which Vincent O'Dempsey and Garry Dubois were convicted of killing Barbara McCulkin and her two daughters.
The trials heard the killings may have been motivated over fears Ms McCulkin would try to implicate O'Dempsey in the firebombing.
Mr Ryan is set to determine whether Finch and John Andrew Stuart who were both sentenced to life over the attack were the only people who caused or contributed to the deaths.
Mr Keim said evidence suggests O'Dempsey - who is expected to be a key witness - wasn't present or active in starting the fire, but "was involved in organising other people to carry out the attack".
More than 60 patrons and staff tried to escape the bustling nightclub in Brisbane's Fortitude Valley after two drums of fuel were thrown into the downstairs foyer and set alight about 2am on March 8.
Fifteen people didn't make it out, dying from carbon monoxide poisoning.
The inquest continues on Monday, with a further sitting due to be held in May.
