A woman who was acquitted of attempting to murder her abusive husband on the grounds of self-defence is now suing the state of New South Wales for malicious prosecution.

In what has been described as one of the worst cases of domestic violence in Australia, Catherine Smith was bashed, raped, tortured and stalked by her husband, Kevin Smith, over a 30-year period.

In an exclusive interview with the ABC, Ms Smith said she should never have been charged and put on trial.

Ms Smith, who lives in hiding, said police and prosecutors knew of her husband's extensive history of violence and that she had acted in defence of herself and her children.

Her barrister, David Baran, said at the time of her arrest it should have been obvious to police that she was suffering from battered wife syndrome.

He said police and prosecutors conducted themselves with "malice" and a "wilful shutting of the eyes" to the obvious flaws in the case.

"This was a woman who was on the brink, and even if it meant having to go and be in jail for the rest of her life, at least [Kevin Smith] would be gone and her children would be spared," Mr Baran said.

Over the course of their 30-year marriage, the mother of six was choked with an electrical cord, shot at with a .22 rifle, tortured with a cattle prod and threatened with a burning fire poker, knives and guns.

Ms Smith called the police for help 18 times but her husband was never charged.

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'I slept with one eye open'

She told the ABC being married to Smith was like being in a prison camp.

"The abuse was intermittent and you'd just never know when it was going to happen or why," she said.

"I used to say I slept with one eye open. I hardly ever slept. Every little tiny sound you'd just jump.

"The police did a risk assessment and they weren't allowed to come to my house or to our aid unless there was four police officers present and it was in daylight hours because they felt he was too volatile for their safety, and yet they left us in it.

"It's hard to fathom, isn't it?"

In 1997, once all their children had left home, Ms Smith left her husband. But she said he continued to stalk the family.

"He had private detectives looking for me, he was trying to blackmail my children into giving me up," she said.

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"Most of my children didn't even know where I was at any given time because they felt it was too dangerous for them to know.

"He just rode the kids and made their life hell. Most of them moved, went into hiding to keep away from him. They were terrified of him as well."

Jury acquitted tormented woman in 25 minutes

It was only when Smith kidnapped their son and held him at gunpoint in 2000 that he was finally arrested.

At the time he made verbal and written threats to kill his wife and their children.

He was jailed for six years and Ms Smith said the family felt safe for the first time.

Kevin Smith was sentenced in 2011 to 17 years with a non-parole period of 10 years.

But as Smith's parole date drew closer, Ms Smith said she became increasingly anxious and bought a pistol.

When he was released, she watched him for two weeks, reporting his movements back to her children.

Then she confronted him with the gun but said she was unable to pull the trigger. They struggled and the gun went off but no-one was injured.

She was charged with his attempted murder and faced trial in 2008.

The jury heard shocking details of Ms Smith's abuse during the marriage and it took them just 25 minutes to acquit her of the charge. Court staff were reportedly in tears as the verdict was read out.

After the acquittal, Kevin Smith was charged with 17 offences, including the attempted murder of Ms Smith.

The trial judge, Leonie Flannery, said Ms Smith had lived in a state of perpetual fear.

Smith was sentenced in 2011 to 17 years, with a non-parole period of 10 years.

Ms Smith's malicious prosecution claim is set down for a three-week hearing in the NSW Supreme Court in July.