A country property in Cushnie

The last confirmed sighting of Susan Thomson was when she visited her GP in Kingaroy QLD on December 22, 1999. She was 49 years old. There has been no contact to family or friends since this time. Susan lived a reclusive life with her husband on their property at Cushnie, between Kingaroy and Murgon. He did not report Susan missing.

If you have any information about the disappearance of Susan Thomson please call 1800 333 000

The enduring mystery of Susan Thomson's life and disappearance

By crime editor Paula Doneman ABC

August 1st 2021



Arthur Thomson's message:  "RING 000. WE ARE BOTH DEAD. MUM IN BEDROOM. ME IN SHED. THANKS."Time of death marked on a wall calendar


The letter Susan Thomson wrote to her mother and the reply

The message was simple.


The sign was crudely taped above the electricity meter under the sprawling Queenslander that was home to Arthur Thomson, 64, in the small farming district of Cushnie, halfway between Kingaroy and Murgon in the South Burnett.

Police believe Mr Thomson anticipated the meter reader would see his note and raise the alarm.

Not far from the sign, he left in cash the exact amount owing to pay their electricity bill.

Alongside the bill on a dresser, possibly to assist police with identification, were the passports of Mr Thomson and his mother, Isabella.

However, the meter man never saw the note.

Instead, two local men, one of whom was a friend and concerned for Mr Thomson's welfare, made the grim discovery on the night of August 26, 2006.

They found Isabella, 86, neatly and tightly tucked into her bed.

Police would later discover her son had marked her death on a 2006 calendar as 1:30am, August 15, before taking his own life in a nearby shed.

Detectives Paul Austin and David Barron, who investigated the deaths while stationed at Murgon CIB, initially thought it could be a murder-suicide.

However, post-mortem examinations revealed Isabella had died of natural causes before Mr Thomson killed himself.

Museum-like house with price tags on furniture

There was no suicide note and not much insight into the reclusive family.

Detective Senior Sergeant Barron described the house as being almost like a museum, with antique furniture in pristine condition, price tags in English pounds still attached  possibly pieces brought with them when toddler Arthur emigrated to Australia with his parents.

There were no photographs.

Detective Senior Sergeant Barron, now stationed at Mount Isa, said the remoteness of the house added to its eerie atmosphere.

But a letter buried in a box at the bottom of a wardrobe revealed Mr Thomson had a de facto wife  Susan Ellen Thomson, nee Warren.

It was the only evidence of her existence.

Police found no trace of her or their 34-year relationship in the house.

The handwritten letter, dated November 8, 1999, was from Susan to her mother, Marie Shaw, telling her she could not ring her as the call would come up on the phone bill.

Susan had asked her mother to write a letter back detailing the day her stepfather died and his funeral.

She also instructed her mother to sign her letters "mum" not "love mum".

"Keep it simple and straightforward (he will read it)," Susan had written.

"I don't know when something might happen but things are very strained; one day things OK, next day at each other's throats (when hes (sic) home)."

The letter disturbed the detectives enough to launch a missing persons investigation.

"That's certainly unusual for a daughter to say to her mother," Inspector Austin, now stationed in Brisbane, explained.

"I suppose the fact Susan was concerned for her own welfare, that if Arthur was in her presence when her mother rang, Susan would say it was a wrong number or if Arthur answered the call, her mother was to hang up immediately.

Mrs Shaw told the detectives her daughter had met Mr Thomson  a garbage collector eight years her senior in 1965, when she was a 15-year-old apprentice hairdresser living in Sydney.

Little known of Susan's 'reclusive life'

Susan left home and did not contact her mother and stepfather Lawrence Shaw for five years.

"We didn't like Arthur at the start because he was a know-it-all type of lad,'' her mother told police.

Eventually Mrs Shaw and Susan resumed contact and Mrs Shaw and her husband then moved to the town of Kilkivan on Queensland's Sunshine Coast around 1984 to be near her daughter and Mr Thomson.

At the time, the couple were living with Mr Thomson's widowed mother Isabella.

In her statement to police, Mrs Shaw remembered Isabella as a "very nice lady''.

"Arthur and Susan always seemed to be happy [and] it was good at the beginning, but it became hard to handle for Susan, living with Isabella like they were,'' Mrs Shaw said in her statement.

Mrs Shaw and her husband moved to Tasmania in 1986, but kept in regular contact with Susan by phone and letter.

Detective Senior Sergeant Barron said insight into Susan's life was limited as she had no friends, did not work, and on the rare occasions she left the Cushnie property, she was always with Mr Thomson and her interactions were cursory.

"Susan had been with Arthur since she was 15, he was eight years older than her so there was a disparity in age and maturity," he said.

"They lived in a small town where everyone knows each other's gossip but no-one really knew anything about them."

Mrs Shaw told police the last time she spoke to Susan was over the phone in late 1999.

"She said words to the effect, 'I have seen Isabella doing something, but I will tell you when I see you','' Mrs Shaw said in her police statement.

The search for missing Susan

By October 2006, police were using cadaver dogs to search the couple's properties at Cushnie and Kilkivan, following a trail that was seven years cold and peppered with conflicting information.

Investigators wondered how a photocopy of Susan's letter came to be in her husband's possession as Mrs Shaw had told them she did not give him a copy.

It also raised questions as to why Mr Thomson kept a letter that painted him in a poor light and potentially incriminated him in his wife's disappearance.

Police also found documents in Mr Thomson's belongings revealing that in 1975, 10 years into his relationship with Susan, a doctor had referred him to a psychiatrist.

There was no police record of domestic violence between the couple, but the Murgon detectives' investigation found Mr Thomson to be a very headstrong and controlling man.

He occasionally drank in local hotels but mostly without Susan and if he had visitors at home, they would drink in the shed.

The investigators' background checks on Mr Thomson with NSW police revealed he had previous convictions for violence when he was young.

Detective Senior Sergeant Barron filed a missing persons report on Susan something her husband never did.

Mr Thomson ignored legal advice he sought in 2005 that to sell the couple's Cushnie property he had to report his wife missing.

Police failed to find anything and also searched under the different names Susan used during her life including her maiden name of Warren and her stepfather's surname of Shaw and although they were not married, the deed to the Cushnie property was under the names of Susan and Arthur Thomson.

The last confirmed sighting of Susan was when she visited her GP in Kingaroy on December 22, 1999, when she was 49 years old. 

But by 2006, her patient records were unavailable as they had been destroyed after the mandatory seven years retention.

Her disappearance almost went unnoticed.

Different versions of why Susan 'left'

The detectives found that Mr Thomson gave different versions of how Susan had left him.

During an unannounced visit to Mrs Shaw's Tasmanian home in 2000, Mr Thomson told her Susan left him while they were shopping for groceries at Gympie.

Mr Thomson claimed Susan started to dress better and wear make-up because she may have been seeing someone else.

His visit prompted Mrs Shaw to report Susan missing, but that report was not passed on to Queensland police. 

In 2000, Mr Thomson told his employer he dropped Susan off at a bus stop in Kingaroy in the early hours of the morning after they had argued about his dogs.

He told his friend Steven Thomas he returned home one day and found Susan gone, and that "what Sue did to me has dropped me on my knees, and I don't think I will ever recover".

The police investigation also found other inconsistencies in what Mr Thomson revealed about himself. He told one friend he was an only child, and told another he had a brother.

Another friend, Kingsley Ferris, told police Mr Thomson appeared to have a "lot on his mind in relation to caring for his mother".

"Arthur once told me he was doing penance now for things he had done in the past. When he said that, he was referring to looking after his mother,'' Mr Ferris said in his statement.

"I could see Arthur cared deeply for his mother, however having to look after her restricted him in what he could do."

In a fourth version while seeking legal advice in 2005 on how to sell the couple's jointly-owned Cushnie property, Mr Thomson told a solicitor that Susan had disappeared.

Police found a letter at the Cushnie property from a Gympie law firm advising Mr Thomson about the sale of the property and "the issues surrounding the disappearance of Susan Ellen Thomsen".

Oddly, the deed for the Cushnie property spells both their surnames as Thomsen.

Mr Thomson ignored the legal advice that to sell the property he would have to report Susan as missing, apply to a court to place the property in a trust, or a separate application asking for a court order that his wife was presumed dead based on her having no contact with anyone for seven years.

Public Trustee searches for Susan

The 2006 police investigation exhausted all leads and Susan's case was referred to the state coroner.

In 2007, a coroner issued a death certificate for Susan but was unable to determine the cause, date and place of her death.

In 2009 and 2014, as there were no wills for the Thomsons' estate, the Public Trustee advertised in newspapers for Susan or anyone who knew of her whereabouts, to contact them. There was no response.

In 2014, to administer the proceeds of Mr Thomson's will, the Public Trustee applied to the Supreme Court as to whether, on the balance of probabilities, he had unlawfully killed Susan.

The court found there was insufficient evidence Mr Thomson had killed Susan or that she died in late 1999 or early 2000.

The court also found Susan could have started a new life under a different name and if her husband's claim she was in a new relationship was true, it could explain why she had not contacted anyone or accessed her personal accounts.

The court also found those who witnessed the couple together spoke of them having a good relationship and evidence of domestic violence was "scant".

Inspector Austin said there had been no sign of life from Susan since December 1999.

"We looked at all the facets of the investigation as to whether Susan had left Arthur," he said.

'Almost like a prisoner'

Police received new information last year that further fuelled their suspicions about Mr Thomson's controlling nature.

Mrs Shaw confided in her carer and friend that Susan described her life as "almost like a prisoner" as her husband forced her to look after her ailing mother-in-law, who was housebound with severe arthritis.

Detective Senior Sergeant Barron said Mrs Shaw, who died in May 2020, was often overwhelmed with grief when dealing with police and found it difficult to talk openly about her only child.

"[The carer] also said Marie's health began to deteriorate just after Arthur Thomson visited her in Tasmania in 2000, claiming he was looking for Susan," Detective Senior Sergeant Barron said.

The carer said Arthur even checked over Mrs Shaw's back fence as if to make sure Susan was not hiding there, and that Mrs Shaw's concerns for Susan's wellbeing became more dire after that visit.

"She could not understand why Arthur had come to her place," Detective Senior Sergeant Barron said.

"She thought Arthur was accusing her of lying about Susan's whereabouts to help build himself an alibi and a facade of being a worried husband."

Queensland police said Susan Thomson's disappearance is being treated as an open missing person's case.

This week is National Missing Person's Week. If you have any information on a missing person, call 1800 333 000.