The Big Read: Case of Donella Knox who murdered autistic daughter Ruby a 'once in a generation case'

For 20 years, single mum Donella Knox doted on her daughter Ruby. She gave her only child unadulterated love and care. In return, she was bitten, headbutted, scratched, tackled, and ignored by a big, strong girl who weighed 70kg by the time she was 9.

Ruby Isabella Knox, born in Blenheim on January 8, 1996, was severely intellectually disabled and diagnosed with severe autism spectrum disorder. She also suffered from a litany of health problems, including chronic constipation and haemorrhoids, incontinence, spina bifida, gastroesophageal reflux disease, asthma, rhinitis, menstrual difficulties, and hip pain. She couldn't talk, nor did she have any ability to empathise.

Ruby was prone to killing pets or small animals. The pair couldn't enjoy play dates or socialise with other families. Instead, they were all alone in their Blenheim state house.

But none of that ever seemed to bother her mum. Their family GP said that in more than 150 consultations, he never saw Donella adversely react to Ruby's violent and sudden outbursts. Instead, all he saw was a mother who loved her daughter dearly; one who was fighting tooth and nail to get the best health care for her that she could.

Donella Knox felt endlessly helpless, and hopeless, about Ruby's deteriorating health and suffering. She felt forgotten about and ignored by the health and care systems.

She travelled across New Zealand, and even to the United States, seeking expert help. Isolated, exhausted and depressed, she often wondered if things would ever get better.

Even when Ruby was 5, Donella spoke of ending it all, for both of them, by driving their car over a cliff edge.

In her harrowing book, Rubies and Pearls, Donella reveals how she would become so frustrated at their plight, that she would have thoughts of "blowing up the hospital" or of taking "serious violent action".

At the age of 6, Ruby Knox was diagnosed with severe autism spectrum disorder.

A diary entry on October 4, 2001, graphically outlines her frustration with trying to get specialist help for her then 5-year old daughter.

"When my rage comes I find myself spinning out, surging, the anger comes and I sit on it and sit on it," she writes.

"Trying to keep civil and not burden an old passer by with my s*** or anger. I feel I have to make myself numb so I don't lose it and spin out of orbit."

On May 16 last year, she finally snapped. She murdered Ruby.

A letter had arrived in the post that morning from doctors saying they could find "no obvious reason" for Ruby's seemingly worsening pain.

Justice Joe Williams who last December at the High Court in Blenheim jailed Donella to four years in jail for Ruby's murder, said it appeared that the letter was "a trigger for your decision to take Ruby's life".

At around 1pm that day, she sedated Ruby with 20.5mgs of risperidone anti-psychotic medication before placing both hands over her face and nose until her breathing stopped.

Donella then went to Blenheim police station and gave a full confession.

It had been coming.

Donella Knox self-published Rubies and Pearls. Photo / Supplied

The last two times Donella's brother Danny Knox had seen her, she had cried. He said that was out of character for her and took it as a sign that she was desperate.

In the six months leading up to the killing, Ruby's functioning had deteriorated further. She had become even more disruptive and violent.

Sleep-deprived and exhausted, Donella took Ruby to her local hospital's emergency department 10 times between February and May last year, claiming her daughter was in pain but could not communicate it.

After leaving hospital, in what would be the last time, a doctor asked a clearly stressed Donella if there was any chance she would do Ruby any harm. She said no, there wasn't.

A social worker phoned the next day. Donella told her: "You're just one of them. I don't know who to trust. I'm done with talking. We're fine, thank you," and she hung up.

One of Donella's friends, who also has a disabled daughter, was another who saw their situation spiralling out of control.

Two months before Ruby's death, Donella told her friend that she and Ruby were hardly sleeping, and that hospital staff hadn't been taking her concerns "seriously or urgently".

"[Donella] fought harder than anyone I know for a good life for her child, and fought alone, and put her own needs aside for Ruby," the friend said.

Donella asked for help from everyone she could think of, the friend claimed.

Donella Knox was a solo mum taking care of her daughter Ruby, living alone in a Blenheim state house. Photo / Supplied

She felt Donella had been "failed systematically by a narrow-minded body of people" who "took a step away instead of taking a step closer".

Health and support workers told the court of a different perspective.

Medical professionals denied that the system had painted Donella into a corner. They said that 252 days a year of respite care was made available to her - a higher allocation than anyone else on their books. She could also choose the carer. Health records show Donella was getting "regular and sufficient" breaks away from Ruby.

One support worker told the court Donella had rejected residential respite options and was a person who "dwelt on the past".

At sentencing, Justice Williams said it wasn't his job to judge the support offered by the health system, but rather to determine whether Donella had genuinely believed she had been let down by the system.

He concluded her beliefs were genuine and deeply felt.

"In your mind, Ruby's unresolved pain and the burden that placed on you... left you with no viable alternative," he said.

"You felt that nobody in authority really felt your or Ruby's suffering and that was the problem. Beyond that, the right and wrong of it, is not relevant to me."

Defence counsel Simon Shamy said there was no doubt over the love that Donella had for her daughter.

But feelings of isolation and being trapped, along with the stress and anxiety over the welfare and care of Ruby, meant she had "felt cornered into taking this most terrible action for Ruby's sake and her own".

Justice Williams said he had traversed the pair's background, and events leading up to the death, in great detail.

Ruby Knox as a young child. Photo / Supplied

"In going through that exercise, I became very sure of one thing: to send you to life imprisonment for Ruby's murder would clearly be inappropriate, or in the words of the law, manifestly unjust," he said.

"While human life is precious, it shouldn't blind us to the particulars of the case before the court. You had full-time solo care for 20 years. You battled the system .. you felt the system had let you down for 20 years... This in my view is a once-in-a-generation case."

The Crown had argued a jail term of 8-10 years would have been appropriate and had indicated it would appeal the four-year sentence.

Crown prosecutor Mark O'Donaghue said Knox "did have other options" at the time, including respite care, residential respite care, and home health support.

Amy Elston, a close friend of Donella's, watched her "give up her life" to care for Ruby.

"Going to jail [is] probably a rest compared to what she's been doing," she said.

"It was a jail sentence every day."

- Additional reporting: Kirsty Johnston