A former prison guard accused of murdering three friends on an outback motorcycle adventure 40 years ago has made a second bid for bail.
Former prison officer Preston was "doing it tough in custody" where he had to be kept in isolation, his barrister said
Bruce John Preston was charged in April with the 1978 murders of Karen Edwards,Timothy Thomson,and Gordon Twaddle, at Spear Creek near Mount Isa.
Preston was "doing it tough in custody" where he had to be kept in isolation because he is a retired senior prison officer, his barrister Russell Pearce told a Brisbane court on Friday.
The court heard that a police report from 1980 had emerged since Preston first applied for bail in June.
Mr Pearce said the Crown's case was "very weak" and contained a lot of "conjecture and innuendo".
Preston had been a person of interest after having been found in possession of a distinctive BMW 750 motorcycle belonging to Mr Thomson weeks after the murders.
The three friends were last seen at a caravan park on the morning of October 5 following their arrival in Mount Isa as part of a motorcycle journey from Alice Springs to Melbourne.
Mr Preston, then an unemployed diesel mechanic, was a suspect early on in the investigation, having been convicted and fined for stealing one of the victim's motorcycles in 1978.
Mr Preston, who had since worked at the supermax Goulburn jail, had been awarded a commendation for brave conduct by the NSW commissioner of corrective services in 2002.
A former Mount Isa local, Mr Preston was charged with the murders of Karen Edwards, 23, Tim Thomson, 31, and Gordon Twaddle, 21.
The trio were found slain in the long grass near Mount Isa in 1978, weeks after they were shot in the head at close range by a .22 calibre rifle and stripped of identification, with their pockets turned inside out.
Weeks after the bodies were discovered, Mr Preston was convicted and fined after he was caught driving one of the victim's motorcycles.
After stealing the bike, Mr Preston had it cleaned, the wheels changed and removed the pannier bags.