Perth 1986: Birnies' terror, four murders, an escape

In the autumn of 1986, Perth, a city in Australia, was shaken by a wave of fear when David and Catherine Birnie, a seemingly ordinary married couple, were exposed as the cold-blooded perpetrators behind a series of brutal kidnappings, rapes, and murders.

For five fateful weeks, their house at 3 Moorhouse Street in the suburb of Willagee was transformed into a veritable torture chamber. Four young women, aged 15 to 31, suffered a gruesome fate there; they were held captive, subjected to systematic torture, and ultimately killed under circumstances that shocked even experienced investigators in Australian criminal history. Their bodies were subsequently dumped in remote forest areas.

It was the desperate escape of a fifth victim, a young woman, that finally put an end to the Birnies' macabre spree and exposed them as serial killers.

David and Catherine's dark past: psychopathic bond

David John Birnie and Catherine Margaret Harrison met as 12-year-olds in a suburb of Perth. Even then, a mutual fascination with transgressive behavior was budding.

David Birnie's psychopathy and sadism manifested early, with animal abuse and burglaries in his teenage years. Catherine Birnie developed a morbid obsession with him. Although she was briefly married to another man and had seven children, she resumed her relationship with David in 1985, shortly after his release from prison for assault and theft.

Their dynamic was disturbing: David's manipulative abilities, a sign of his psychopathy, and Catherine's cunning talent for luring victims into their trap. Forensic psychologists later described Catherine Birnie as David's female counterpart – a master at gaining trust, which made her indispensable in the couple's criminal career, which also included numerous burglaries.

First victim Mary Neilson: tortured and killed in forest

The couple's systematic modus operandi for murder began on October 6, 1986. Mary Neilson, 22, stranded with a broken-down car, met Catherine Birnie at a petrol station. With feigned compassion, Catherine offered help but instead lured Neilson to the house in Willagee.

There, in the bedroom, which had become a scene of horrors, she was handcuffed to the bed and repeatedly raped by David Birnie, encouraged by Catherine. After 24 hours of torture and captivity, the couple drove her to Gleneagle State Forest. There, she was raped again before Catherine tightened a nylon strap around her neck. David cut her throat – allegedly to hasten decomposition – after which they buried her in a shallow grave.

This was the first of several brutal murders.

Susannah Candy: 36 hours of hell, a brutal filmed murder

On October 20, just fourteen days later, 15-year-old high school student Susannah Candy became the Birnies' next victim. She was lured into their car on Stirling Highway, where Catherine Birnie threatened her with a knife while David Birnie tied her up.

In the house on Moorhouse Street, Candy endured 36 hours of torture and coercion. Among other things, she was forced to write a letter to her parents about a feigned escape. Catherine's active participation in the abuse escalated; she attempted to strangle Candy with a cord. When this failed, they forced the girl to swallow sleeping pills.

While Susannah Candy was unconscious, Catherine tightened the cord around her neck, a macabre murder that David filmed.

Noelene Patterson: three days of jealousy-driven torture

On November 3, 31-year-old bartender Noelene Patterson became the third victim. Her car broke down on Canning Highway, and David and Catherine Birnie again offered "help."

This led to three days of marathon torture in their home. Catherine Birnie's jealousy over Patterson's education and self-confidence allegedly led her to insist on a particularly brutal end to this murder. Noelene Patterson was driven to Wanneroo Pine Plantation. There, David Birnie cut her throat during a rape, while Catherine stood guard, armed with an axe.

Another murder carried out with appalling sadism.

Denise Brown: deceptive ride and axe murder in Modup

Just two days later, on November 5, the Birnies found their fourth victim: 21-year-old university student Denise Brown. She was waiting for a bus when Catherine Birnie offered her a ride. In the car, David Birnie tore off her clothes with a knife, an act Catherine filmed.

In the house on Moorhouse Street, Brown was fitted with a collar and chain, a symbol of the couple's ownership and her total captivity. In Modup Forest, Denise Brown was subjected to a final rape. David cut her neck.

When she shockingly rose from the grave they had prepared, Catherine grabbed an axe and struck her twice in the skull, completing the fourth murder in this series of crimes committed by the serial killers.

Kate Moir's escape: 17-year-old reveals the horrors

The turning point in this Australian case came on November 9, 1986, with 17-year-old Kate Moir. After being raped and held captive for 12 hours in the house, she persuaded David and Catherine Birnie to let her go to the toilet alone. There, she managed to break a small window and escape.

Her desperate run through the streets of Willagee led her to neighbors, who immediately alerted the police. During questioning, Kate Moir provided a detailed description of the house's interior, including the location of a key to the handcuffs.

When police arrived at the crime scene at 3 Moorhouse Street early the next morning, they found Catherine Birnie removing bloodstains from the bed linen – macabre evidence from this central crime scene.

Aftermath: trial, David's suicide, Catherine in prison

During subsequent interrogations, David Birnie and Catherine Birnie showed a frightening lack of remorse and a chilling pride in their actions, a trait often seen in psychopathy. David even offered to show the police where the victims of their murders were buried, with the cynical comment that they were "better at it" than the police.

The trial in February 1987 became a media spectacle, where the Birnies maintained their cold facade. David Birnie's statement that he would "spare the families a long trial" by pleading guilty was met with contempt. In prison, David Birnie committed suicide in 2005 by hanging. Catherine Birnie continues to serve her sentence and is described as a model prisoner. Her applications for parole have been repeatedly denied, most recently in 2016, partly due to pressure from the victims' families and a campaign led by survivor Kate Moir.

In 2020, the house on Moorhouse Street, the scene of so much torture, was sold to a family reportedly unaware of its dark past. Although the house has been renovated, the case of David and Catherine Birnie lives on. As recently as 2024, aspects of the case have become relevant in connection with a new trial concerning an unsolved case of a woman who disappeared in 1986, where defense lawyers have suggested the Birnies' possible involvement.

David and Catherine Birnie's morbid symbiosis and their modus operandi are today considered a frightening prototype of the "team killing" phenomenon – a form of partner-related serial crime that continues to challenge the justice system. For the survivors and relatives, the fight for justice continues in the shadow of one of Australia's most shocking criminal cases, a case that stands as a dark chapter in Australian criminal history.

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