Woman who claimed partner killed himself over his sexuality found guilty of murder

A woman in New South Wales, Australia, was found guilty today of murdering her partner in 2017.

Natasha Beth Darcy, 46, met sheep farmer Mathew Dunbar, 42, via an online dating site in 2014. Those who knew Dunbar said he desperately wanted love and a family. Instead, Dunbar died on August 2, 2017.

Darcy has always claimed that Dunbar took his own life by gassing himself. She said he had been depressed for some time. She had told friends he struggled with mental health issues, was facing possible amputation because of a leg injury, and that he was gay.

However, authorities were immediately suspicious of her version of events. They quickly discovered that Dunbar had been heavily sedated before his death, leading them to believe that Darcy was involved.

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When they checked her phone, they found hundreds of Google searches on such topics as poisonous spiders, fungi, suicide, “plastic bag suffocation”, “Can police see deleted text messages” and “How to commit murder.”

Her ten-week court case began at the end of March. During the trial, the jury heard:

• Darcy began badgering Dunbar just months after meeting him to change his will and leave his estate to her. His sheep farm in the small town of Walcha was worth around AU$3.5 million ($2.7million).

• During her relationship with Dunbar, Darcy had been sent back to jail for breaching parole. She had previously been found guilty of trying to kill her first husband, paramedic Colin Crossman, in 2009 by hitting him over the head with a hammer, sedating him, and setting his home alight. He survived. In a bizarre coincidence, Crossman was among the first responders to show up at the Dunbar crime scene.

• Dunbar had been emotionally manipulated and gaslit by Darcy throughout much of their relationship.

• The prosecution accused Darcy of using a Nutribullet to blend up a cocktail of sedatives, which she gave to Dunbar. She then used helium to suffocate him. On the night of his death, she searched “Does helium show up in an autopsy?” on her phone.

• Before Dunbar’s death, Darcy had conducted two “dry runs”. The first time she’d injected ram sedative into Dunbar’s leg, and the second she’d given him an overdose of her son’s medication.

• Just before his death, Darcy bought a large amount of ram sedative from a local veterinary store. She also bought a tank of Helium. She called a local store, Supagas, and placed an order for the helium, telling them that Dunbar would be in to collect it. Darcy denied calling the store and said it had been Dunbar, arguing “Mathew had a very feminine-sounding voice”. The store employee told the court, “No, I am 100 per cent certain I spoke to a woman.”

• On remand for murder, Darcy – inspired by an old episode of Frasier – wrote to a friend to ask them to make a false statement about Dunbar planning to kill himself, in exchange for AU$20,000. “I was watching an episode of Frasier when Niles needed him to lie in court and say he didn’t know that Niles was in love with Daphne. It got me thinking if only I could ask somebody to say that Mathew told them he was planning his suicide maybe a few or several days before he passed.”

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As the evidence against her began to stack up, Darcy pleaded guilty to aiding and abetting suicide but authorities rejected this and charged her with murder.

The judge in the trial also instructed the jury to put thoughts of assisted suicide out of their mind as there was no evidence this was the case.

The jury took two days to reach its ‘guilty’ verdict. Darcy will be sentenced in October.