Four years ago, Jonda Stephen found herself in a life-or-death situation.

Key points: Jonda Stephen had suffered months of abuse by her partner Chris Tiffin

Jonda Stephen had suffered months of abuse by her partner Chris Tiffin One day, in self-defence, she stabbed Tiffin and killed him

One day, in self-defence, she stabbed Tiffin and killed him The NSW DPP charged Ms Stephen with murder despite a magistrate downgrading the charge to manslaughter

Her partner, Chris Tiffin, had hit her in the head three times with a clothes iron, so she picked up a knife and stabbed him in self-defence.

"We'd been fighting all weekend," she told 7.30.

"I've said, I just can't keep doing this anymore.

"He had my laptop and he was going to smash it and so I just grabbed for it and next thing he's picked up an iron and he's bashing me up against the side of the head.

"And just in the corner of my eye I saw a knife and I've grabbed the knife and I stabbed him."

She stabbed him once.

He stumbled outside and collapsed before Ms Stephen called triple zero.

"I just wanted him to stop beating me with the iron," she said.

But after enduring the unthinkable, came the unimaginable. Broken Hill police charged Ms Stephen with murder.

'Failed by the system'

Chris Tiffin (right) has abused Jonda Stephen for months. ( Supplied: Jonda Stephen )

Ms Stephen spent time in Sydney's maximum security Silverwater prison before being granted bail three-and-a-half months later.

"It's terrible at Silverwater," she said.

"You survive and that's about it."

It is trauma she is now living with as a free woman.

In February last year, a judge instructed a jury to acquit her of both murder and manslaughter.

"I always wished it had've been me instead, because to me the death would have been a lot easier than all the suffering that went afterwards," she said.

Ms Stephen is now suing the New South Wales Government for malicious prosecution. She's hoping her case will prevent other domestic violence victims going through what she did.

"I'm supposed to just forget everything. I'm acquitted and everything's all rosy," she said.

"I suppose if no-one else stands up to the system who is? Who's going to change things? Because this shouldn't happen to people.

"It's not right."

Ms Stephen's lawyer, Pauline Wright, said the case was an example of police failure in domestic violence cases involving self-defence.

"In my view, Jonda was failed by the system," she told 7.30.

"I think what we've got to see, to make sure this kind of thing doesn't happen to other women, is that police do get proper training about domestic violence about the way it makes women behave."

Injuries ignored

The crime scene of the room where Jonda Stephen was attacked by and then stabbed Chris Tiffin. ( Supplied: NSW Police )

From the outset, Ms Stephen told police she had acted in self-defence.

While she told police Tiffin had abused her throughout the relationship, the initial police facts sheet pointed out she never reported her partner's behaviour.

It also claimed she didn't appear remorseful.

Later in the investigation police accessed phone texts between Ms Stephen and her daughter, others were provided by her legal team, which detailed domestic violence in the months leading up to the fatal incident.

Text messages between Jonda Stephen and her daughter, supplied by her legal team as evidence. ( ABC News )

Despite a visible facial injury, Ms Stephen was not taken to hospital the night she was arrested.

She was given paracetamol for a headache.

"My eye felt all crunchy and it was pounding and I know when I was in the jail cell I couldn't lie on one side because my elbow was too sore," she said.

"I couldn't lie on the other side because of my shoulder and I just know I was in a lot of pain."

At one point, she is seen in CCTV footage to slump to the ground in the police holding cell.

Ms Wright said an x-ray, 11 days later in jail, revealed Ms Stephen's eye socket was fractured.

"If Jonda had been given a thorough investigation at the hospital they would have discovered that she had the fractured skull," she said.

"They would have discovered the fractured elbow, they would have discovered the torn shoulder ligament."

'Did you inflict the injury yourself?'

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 28 seconds 1 m 28 s Detectives ask Jonda Stephen whether her injuries are self inflicted

In a second interview, detectives challenged Ms Stephen's claim that she killed Mr Tiffin in self defence and questioned how she had sustained her injuries.

Interviewer: Did you inflict the injury to your eye with the iron yourself? Jonda Stephen: No. Interviewer: Did you stab Chris and then did you stage the crime scene to make it look like a struggle had occurred and inflict the injury upon yourself? JS: No. Interviewer: Earlier you used the words, you murdered Chris. JS: Because that's what I've been charged with.

Ms Stephen's lawyer asked the Police Commissioner to remove the detective in charge, Ryan Jeffcoat, from the case because of alleged bias and a lack of understanding of domestic violence.

Police dismissed the complaint.

"We thought that his view of the case was flawed from the beginning and that he didn't have an independent mind to bring to the investigation or the prosecution," Ms Wright said.

"All I can think is they have no idea about domestic violence, even though they've implemented all this training, because I can't understand how they saw me as being a perpetrator when Chris was twice my size and strength," Ms Stephen said.

Fifteen months after Ms Stephen was charged with murder, a magistrate downgraded the charge to manslaughter.

Despite that, the Department of Public Prosecution (DPP) continued to pursue the murder charge.

"It's really hard to know why the DPP was so intent on prosecuting her for murder even though the evidence corroborated her account of it that it was self-defence," Ms Wright said.

Mr Jeffcoat was medically retired from the NSW Police Force in 2018 suffering from PTSD.

He declined 7.30's request for an interview but said the assertion that Ms Stephen's murder charge resulted from a lack of understanding of self-defence and domestic violence was without merit.

He said the investigation was conducted without bias and ultimately the DPP decided to continue with the murder charge.

It felt like 'a bit of a witch hunt'

Kerri Bellew was a juror in the trial of Jonda Stephen. ( ABC News )

When the trial finally started in February 2018, it heard Tiffin had an extensive criminal record and had abused previous girlfriends.

Nine days into the trial, the prosecution conceded it couldn't prove its case.

The judge instructed the jury to acquit Ms Stephen of both murder and manslaughter.

Kerri Bellew was one of the jurors.

"It was a case that shouldn't have happened, honestly, taxpayers money, her money — her life, really," she told 7.30.

"They should have realised that she was defending herself. It should have stopped there."

She said it felt like someone had it in for Ms Stephen.

"I kind of felt it was a bit of a witch hunt," she said.

"Was it a personal thing from someone who didn't like her? Who just didn't like her on the day? Didn't like her attitude?"

Getting her life back together

Jonda Stephen is now suing a number of agencies over her ordeal. ( ABC News: Lincoln Rothall )

In her statement of claim against the police, the DPP, NSW Ambulance and Corrective Services, Ms Stephen alleges she was maliciously prosecuted, that her injuries went untreated, she was deprived of her liberty and suffered psychiatric injury and reputational damage.

She is also suing the Far West Health Service for unfair dismissal.

When Ms Stephen was charged with murder she was stripped of her working-with-children clearance and sacked from her administrative job at Broken Hill hospital.

"I struggle to get my life back together, to get past that," she said.

"I thought I must have had a brain injury because of my PTSD. It's called disassociation so I'll be driving and drive past the turn-off and don't realise for an hour."

All of the parties named in the civil lawsuit — Police, the DPP, NSW Ambulance and Corrective Services — declined 7.30's requests for interviews, citing the current action.

One agency, NSW Ambulance, has apologised to Ms Stephen about her lack of treatment for her head injury.

"You should have been transported [to hospital] on your first presentation," the letter said.

"As a result of the investigation, a clinical training officer will be meeting with the attending paramedics and providing them with education and counsel relating to this matter.

"I thank you for raising your concerns with us and allowing NSW Ambulance to continually improve the standard of care we deliver to our patients.

"Please accept our sincere regret for any stress that may have been caused as a result of this incident."

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