Queensland 1978 Cold Case Solved – Arrest Shocks Community

An inquest has begun into an Outback Queensland triple murder that has remained unsolved for close to half a century.
>> On the evening of October 24th, 1978, a Mount Isa man named Stan Harris was walking his greyhounds through bushland at Spear Creek, a dry waterway about 12 km north of town.
In the long grass near a tree, he found a decomposing body, a man shot once in the head with a small caliber rifle.
Two more bodies turned up in the spinifex grass the next morning, both killed the same way.
The three of them had been there almost 3 weeks.
In 1978, no laboratory in the world could pull DNA from a body left 3 weeks in Outback heat.
The detectives had what witnesses had seen at a caravan park the morning the three friends disappeared.
They could not turn it into a charge.
47 years later, the same name has been in the file the entire time, and the man who carries it has never been convicted.
Karen Edwards was 23, a trainee medical psychologist from Dandenong in Victoria.
Tim Thompson was 31, a New Zealand school teacher who had moved to teach at a remote Aboriginal community called Hermannsburg near Alice Springs the year before.
Karen was his girlfriend.
Gordon Twaddle was 21, a pastry cook from New Zealand and a family friend of Tim’s.
The three of them had a 9-month-old Doberman puppy with them called Tristy.
On October 2nd, 1978, the three of them left Alice Springs on motorbikes.
Tim and Gordon had been working in the Northern Territory and were heading home.
Karen had flown up to Alice Springs to meet them for the trip.
Her sister Robin later told reporters Karen had been excited about seeing Tim again after months apart.
Tim and Gordon were both motorbike enthusiasts who shared a passion for vintage machines.
Tim and Karen rode together on a red and gold 1977 BMW with a homemade sidecar that carried Tristy and most of their gear.
Gordon rode a blue 1977 Suzuki with a racing cowling.
The plan was to ride north and east to Mount Isa, then turn through Cairns and follow the coast down to Melbourne in time for Christmas.
They stopped at Aleron on the first day and camped overnight at Tea Tree in the Northern Territory.
A tourist took a photograph of the three of them along the way, the last one ever taken.
The road they were on cut through some of the emptiest country in Australia.
Towns hours apart, the next house on the highway sometimes 100 km away.
They reached the Outback mining town of Mount Isa on October 4th.
They were experienced travelers, the bikes were well-loaded, and the dog was riding in his sidecar.
By the morning of October 5th, the three of them were camped at the Moondarra Caravan Park, a popular stopover about 20 km north of Mount Isa.
The reservoir there drew backpackers, long-distance travelers, and locals using the lake for fishing.
Witnesses at the campsite saw the three friends in the company of another man.
He was dark-haired and bearded, and he was driving a brown and white Toyota Land Cruiser station wagon.
The man had been seen with their group on the road earlier and had now caught up to them at the caravan park.
At some point that morning, the three friends climbed into the vehicle with him and drove off.
They left their gear and their motorbikes at the campsite and tied Tristy to a tree.
The plan, as far as anyone at the park knew, was a short outing.
They never came back.
Later that day, the same Land Cruiser returned to the caravan park.
The man inside was alone now.
He was heard calling out for the dog by name, Tristy, over and over as he packed up the trio’s belongings.
By dawn the next morning, October 6th, Tristy had been found alive at the town tip by workers arriving for the day.
The trio’s helmets, jackets, gloves, and tents were stuffed into a 44-gallon drum at the same tip.
Gordon’s blue Suzuki was found abandoned at a service station in town with the keys still in the ignition.
Tim’s red BMW had vanished.
For almost 3 weeks, no one in the trio’s families knew yet that anything was wrong.
Days of silence between letters home were normal at that distance.
Their parents in Melbourne and in New Zealand were waiting for the next postcard, the next phone call from a roadhouse somewhere on the route east.
The bodies turned up at Speer Creek on the evening of October 24th in dry country of spinifex grass, low trees, and red earth.
The rest of the picture came together over the next 48 hours.
Tim Thompson was the one against the tree.
He had been shot once in the head at close range with a .22 caliber rifle.
The next day, police searching the surrounding bush located Karen and Gordon lying together in a clump of spinifex grass about 100 m away.
Both had been shot the same way.
The autopsy put time of death at around October 5th, the same day the trio had been picked up.
The pockets of all three victims had been turned inside out.
Wallets, watches, jewelry, anything that might identify them was gone.
The bodies were so badly decomposed after 3 weeks in the Outback heat that police could not put names to them straight away.
Identification came through a tiny woman’s watch the killer had missed in the long grass.
The band was broken.
Inside the case, police found service inscriptions MG8/78OH that pointed back to a jeweler’s mark from earlier that year.
Police released the photograph of the watch and the markings to newspapers across the country hoping a relative would recognize them.
Karen’s father, Jack, in Victoria, identified the watch as his daughter’s.
Karen was confirmed through her dental records and Tim and Gordon through their fingerprints.
By the start of November 1978, the three bodies in the bush had their names.
While investigators were still working the scene, a police helicopter surveying the bush from the air crashed near the site.
Several officers on board were badly injured and resources had to be diverted to the crash itself.
The investigation lost momentum almost as soon as it had begun.
What detectives could put together from the wider evidence pointed to a local.
Whoever had done this knew where the tip was and where the service stations were.
He knew the bush north of town well enough to take three strangers there and leave them out of sight.
He had access to a vehicle big enough to carry three people, three bikes worth of gear, and a dog.
They were looking for someone who lived in Mount Isa.
The annual Mount Isa Rodeo had just ended when the murders happened.
The town’s population had swelled with weekend visitors who had now scattered back to their own corners of the Outback.
Tracking who had been where on October 5th was almost impossible.
Police could not identify the three bodies straight away.
No missing persons reports matched and most of what was left in the bush had been lost to weather and time.
Retired homicide detective Jim O’Donnell, who worked the case in 1978, still thinks about it.
“Why didn’t we do this?”
He has asked himself for 45 years.
“Why didn’t we do that?”
On 13th November 1978, less than a month after the bodies were found, a 23-year-old local was arrested in possession of Tim Thompson’s missing red BMW.
The man had been riding it openly around town.
He told police he had bought it second-hand, but later admitted he had stolen it, pleaded guilty, and was fined $300.
By the time police got their hands on the bike, he had cleaned it, changed the wheels, and stripped some parts off.
No further charges were laid.
The detectives running the murder investigation were now looking at a 23-year-old who could not be tied to anything beyond the theft.
They had a suspect they could not arrest and a bike in his garage that proved nothing on its own.
The murder case and the bike theft never came together in court.
The young local’s name was Bruce John Preston.
His father Arthur Preston was a well-known figure in town.
Arthur worked as a chief trainer at Mount Isa mines and ran the underground inductions for almost everyone who passed through the mine.
One local later described him as an army drill sergeant straight out of a movie.
He owned a brown and white Toyota Land Cruiser station wagon and the family who lived nearby in town were all hunters with a number of firearms in the house including a .22 pump-action rifle.
His older brother Ian told a court many years afterward that the entire family was very familiar with guns and that Bruce in particular was a crack shot.
He was also a member of the Black Uhlans, an outlaw motorcycle gang.
His physical description matched the dark-haired, bearded man witnesses had seen at the caravan park.
He had access to his father’s Land Cruiser.
The household firearm matched the caliber of the weapon used at Spear Creek.
The dead man’s motorcycle had been found in his garage weeks after the killings.
In 1978, police examined the Land Cruiser and the firearms at the family’s address.
They interviewed Bruce more than once.
He was a known local who had been on their radar before the BMW arrest.
Witnesses had described a man at the caravan park driving a brown and white station wagon and the car at the Preston address fit on every count.
The voice and build fit, too.
But the forensic technology of the era could not connect any of it to the bodies at Spear Creek.
In 1980, a coronial inquest was held in Brisbane.
It returned a finding of death by an unknown person or persons.
The 1980 record fit Bruce Preston in his father’s vehicle on every line.
The inquest also confirmed what road witnesses had told police.
Somewhere between Alice Springs and Mount Isa, the group had been befriended on the highway by another motorbike rider.
Police believed the same man had then visited the campsite in the station wagon.
The standard of proof required for a criminal charge was higher than what the file could support.
The case went into the cold files of Queensland police and there it stayed.
Decades passed.
Karen’s father, the man who had identified his daughter through the watch, died waiting for answers.
Tim and Gordon’s parents grew older in New Zealand, still expecting the Christmas reunion they had been promised in 1978.
They spent year after year without an answer for what had happened to their sons in the Outback.
Police reviews of the file came and went.
Each one ended in the same place the 1980 inquest had.
Karen’s brother Barry Edwards spoke to reporters in 2019 about what the family had carried for so many years.
“A lot of people in Mount Isa would have known what happened and who did it.”
He said.
“They had not come forward.
” Gordon Twaddle’s older brother John in Mosgiel, New Zealand brought Gordon’s ashes home after the funeral in Brisbane, but never buried them.
He said he was not going to plant his brother’s ashes until they found out who had done it.
The ashes are still above ground.
In Mount Isa, the case stayed alive the way old cases stay alive in small towns.
People talked about it at the pub and the same name kept coming up.
The detectives knew it, too.
Bruce Preston left Mount Isa not long after the murders and built a career in corrections.
He moved to New South Wales and worked his way up to senior prison officer at Goulburn Supermax, the highest security prison in the state and home to some of the country’s most violent inmates.
He held senior rank there for years and retired without incident.
While the murders of three young travelers sat in the Queensland police cold case files, the man named in those files was running a uniform through the Supermax yard every day.
In April 2019, more than 40 years after the bodies were found at Spear Creek, he stepped off a plane in Brisbane.
He was 63, retired from Goulburn Supermax, and not expecting what came next.
Detectives from the Queensland cold case investigation team arrested him at the airport terminal and charged him with three counts of murder.
The arrest was the product of a year-long review led by Detective Senior Sergeant Tara Kentwell.
Her team had gone back through every page of the original 1978 file.
New witness evidence had come forward after a Northwest Star anniversary feature in 2018 brought the case back into public conversation.
Old Mount Isa locals, people who had known the family in 1978, people who had heard things in the years since, came forward with statements the original investigation never had.
Some of them had spent 40 years deciding whether to make that phone call.
For the families of Karen Edwards, Tim Thompson, and Gordon Twaddle, the arrest was what they had been waiting for since 1978.
A name.
>> [clears throat] >> A man in custody.
The charge sheet that set out loud what the file had been suggesting for four decades.
In 2020, he got bail.
Justice Davis of the Supreme Court ruled that investigators had overstated the evidence when they had argued against bail the first time.
The ruling came less than a year into the prosecution.
He returned to Goulburn under curfew, ordered to report to local police three times a week, and to hand in any firearms he owned.
In 2023, four years after the arrest, Queensland prosecutors withdrew all three charges.
The forensic tests that might have linked Preston directly to the bodies either had not been run or had not produced anything that could be put in front of a jury.
Witnesses had died in the years between and the physical evidence was old.
Preston walked out of the case a free man.
He had spent four years on bail, three nights a week at a police station counter and no part of the trial had taken place in open court.
The families of the three victims were left where they had been in 1980, unknown person or persons.
The file went back into the cabinet.
In October 2025, almost 47 years after the killings, Queensland coroner David O’Connell reopened the coronial inquest into the deaths of the three travelers.
The hearing ran for nine days in Brisbane and heard from up to 40 witnesses.
Counsel assisting the coroner, Amelia Hughes, walked the court back through the 1980 finding.
She read aloud from the original record.
The 1980 coroner had been satisfied that the killer was the man who had picked up the three friends at the Lake Mondarra Caravan Park on the morning of October 5th.
He had probably shot them to death the same day.
After 45 years and a fresh cold case investigation, the description on file had not changed.
The 2025 hearing accepted the original cause of death finding without amendment.
Bruce Preston was ordered to give evidence.
At 69 years old and in ill health, he appeared in court in a wheelchair.
The coroner granted him indemnity, meaning whatever he said on the stand could not be used against him in a future criminal trial.
The protection was the price the system paid to put him in the witness box.
The coroner warned him repeatedly that the protection did not extend to lying.
He was, the coroner said, very close to charges of perjury.
He denied any role in the murders.
He admitted again to stealing Tim Thompson’s motorcycle in 1978, but gave conflicting accounts of where, when, and how he had come by it.
Counsel pressed him on his own timeline.
He had told earlier investigators he returned to Mount Isa on October 11th.
Witnesses placed him in town around October 4th or 5th.
He denied trying to push the date later to distance himself from the killings.
His head, he said, had been in a whirl.
He had done a stupid thing.
He had taken something that did not belong to him and kept it, not imagining for 1 second what had actually happened in the bush north of town.
When detectives told him later that the motorcycle had been used in a triple homicide, it had hit him, he said, like a ton of bricks.
He had spent 11 months in an isolation cell after his arrest, and the last few years thinking about nothing else.
The coroner sent him home with a warning.
Have a good think overnight, the coroner said, and come back in the morning with a lot more conviction as to what is truthful.
His older brother Ian Preston took the stand next.
Ian was also threatened with perjury during his evidence and was eventually granted indemnity of his own.
He confirmed the family’s history with firearms and Bruce’s reputation as a shot.
He acknowledged what other witnesses had said about their late father, Arthur Preston, who had spent the rest of his life telling people that his son had done it.
The exact words attributed to Arthur Preston were that the little bastard done it, but he’s a tough little bastard, and they can’t break him.
Ian Preston denied first-hand knowledge of his father saying it.
He conceded those would be the words the old man would use, since Arthur had been a hard man.
He could not deny that the words had been spoken because they had already entered the court record through other witnesses who said they had heard Arthur Preston say them.
The coroner’s findings from the 2025 inquest have not yet been delivered.
The case remains under active investigation by Queensland police.
A reward of $250,000 is still on the table for anyone who can close the gap.
Bruce Preston is the only person ever charged with the murders of Karen Edwards, Tim Thompson, and Gordon Twaddle.
The charges against him have been withdrawn.
He sleeps in his own bed in Goulburn.
The Buchanan’s Creek is still there, 12 km north of Mount Isa, dry and quiet in the long grass.
The three friends rode east out of Alice Springs in October 1978 on a red BMW and a blue Suzuki with a Doberman puppy in a sidecar and a plan to be home for Christmas.
They got as far as a caravan park 20 km north of Mount Isa.
The man who picked them up that morning drove their belongings to the town tip the same night.
Three young people rode into the bush.
None of them rode out.
If this case stayed with you, leave your thoughts in the comments.
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Disclaimer: This story is a work of fiction created for entertainment purposes. Any resemblance to real persons, events, or places is coincidental.