Bruce Preston, 67, charged over the 1978 Spear Creek triple murder, walks free from Supreme Court

The man charged with the 1978 Spear Creek triple murder has left the Supreme Court a free man after all charges against him were dropped.

Bruce John Preston, 67, was charged with the alleged triple murder of Karen Edwards, her boyfriend Timothy Thomson and their friend Gordon Twaddle in 2019 – more than 40 years after their bodies were found.

Police allege the trio of friends were shot in October 1978 in the bush at Spear Creek, outside Mount Isa.

Their bodies were found about 12 km from Mt Isa two weeks later.

They had just started a motorcycle road trip across Australia.

Mr Preston, a retired senior prison officer at NSW’s Goulburn Supermax Prison, was arrested in 2019 after the Queensland Homicide Investigation Unit cold case team reviewed the case.

Mr Preston, who was out on bail when he appeared before the Brisbane High Court on Monday, was formally acquitted of all three murder charges.

The Crown filed a Nolle Prosequi (a formal cease and desist notice) in respect of the charges in court, having determined that it could no longer prosecute the case.

Mr Preston was acquitted of all three murder charges.

The court was told that one of the reasons was that a number of key witnesses had died or were not in good health to testify for a trial.

Prosecutors dropped their cases after key witnesses had a father or were in ill health, telling the Brisbane High Court (pictured) they could not proceed in good faith

Police allege Tim Thompson (left) was shot along with his girlfriend Karen Edwards (center) and their friend Gordon Twaddle (right) in Spear Creek, northeast of Mount Isa.

The Crown Prosecutor told the court that he was not sure when those key witnesses had died.

‘Some information had (also) been provided (which) was incorrect and some vital evidence had been overlooked…therefore there was a decision that any trial, any trial, would have been fundamentally unfair on the basis of public interest’ said the Crown Prosecutor.

“The cases are constantly reviewed and investigated, so that eventually the critical analysis can be revised.”

Mr Preston’s lawyer, Russell Pearce, told the court that his client had always maintained his innocence and cooperated throughout the investigation.

“Prosecution is not proceeding because witnesses have died or witnesses are no longer able to testify due to ill health,” Pearce said.

“I want to record that the defense cooperated throughout this proceeding to ensure that all evidence made its way to a hearing.”

The Moondarra Caravan Park, near Mount Isa, (pictured) where the trio of friends were last seen alive on October 5, 1978

Justice Peter Callaghan said there had been “terrible” communication between police and the Director of Public Prosecutions about the issues surrounding the witness list.

“In this case, there seems to be a clear indication that it just didn’t happen,” Judge Callaghan said, referring to the DPP’s review process.

Supporters of the trio had to accept that the death of their loved one remained unsolved.

Mr Twaddle and Mr Gordon are both originally from New Zealand, and Mr Gordon has also lived in Melbourne and Alice Springs.

Mrs Edwards was from Dandenong in Melbourne before she started travelling.