Australia's 'black widow' acquitted of murder after piercing her partner's heart with the tip of a knife has spoken out, questioning why she had to face court at all.

In a major 60 Minutes report, Lena Kasparian took Tara Brown through the night of horror which saw the life of her abusive partner end and hers destroyed.

To watch '14 MM' in full, head to the 60 Minutes official site.

"It does hurt when people say nasty things about you and call you a murderer when you know you're not," Ms Kasparian told Brown.

"When someone you love dies and you're blamed for it."

To outsiders Ms Kasparian and her partner of 10 months, Marc Zartarian, appeared to be a happy loving couple. But in truth their relationship was falling apart due to Zartarian's heavy drinking and drug taking.

On Sunday the 1^st of May, 2011 the couple had attended a family party but were forced to leave early because Zartarian was drunk.

"I knew he was going to be out of control and he was going to embarrass me and humiliate me," Ms Kasparian told Brown.

"[The drive home was] horrible. It was just intense. He was out of control."

With her two young children in the back of the car, Ms Kasparian rushed them safe and inside the home, telling Zartarian to "cool off" outside.

"He kept yelling and hurling abuse," Ms Kasparian said.

"Trying to kick the door in and running into the door and making a racket."

Concerned with the noise Zartarian was making and what her neighbours would think she let him come inside. A decision she regrets to this day.

"I remember the look on his face it just wasn't him anymore," she said.

Zartarian – who had never previously been physically violent – slapped Ms Kasparian before grabbing a nearby saucepan and beating her repeatedly over the head.

Ms Kasparian's three-year-old son and five-year-old daughter had heard the arguing and came running to their mother's aid.

"I'll never forget my kids screaming," she said.

"Having my son wrapped around my leg screaming and crying and my daughter trying to protect me, kicking Mark from behind telling him, 'Leave my mummy alone.'"

Zartarian lost his grip on the saucepan, giving Ms Kasparian a split second to find an object to protect herself – a 16 centimetre boning knife that had been left in the sink from the night before.

"I grabbed it. Just held it up to my chest and I said, 'Stay away from me,'" she revealed.

"He saw the knife in my hand. He started pacing and chest out, and he just kept saying, 'All right, stab me. Go on, stab me. Do it. Do it.'"

Zartarian stepped forward and the knife pierced his chest by just 14 millimetres – a wound smaller than a paperclip.

"I don't know if he tripped or if he missed a step or if he ... I don't know," Ms Kasparian said.

"But at one point he just came too close, and I'm still holding the knife at my chest, firmly."

"And I think at that point, I realised that the tip of the knife had gone into his shirt. And I think he felt some sort of cut, and we just looked at each other with this gasp."

Ms Kasparian says she grabbed her two distraught children and hid in the laundry before calling emergency services – a call which 60 Minutes were able to air in full.

Ms Kasparian: ‘My boyfriend attacked me and I stabbed him in the chest with a  knife’

Triple Zero: ‘You have stabbed your boyfriend in the chest?’

Ms Kasparian: (children crying) Yeah, because he attacked me with, he was hitting me and…’

Triple Zero: 'What are his injuries to the chest is he bleeding?’

Ms Kasparian: He’s fine, he’s fine. It’s just a small stab wound’

Zartarian was pacing the home and calling friends and yelled that he couldn’t breathe.

The sharp knife had - incredibly - missed cartilage and ribs to pierce his heart.

When police arrived Ms Kasparian declared she was only trying to defend herself and protect her children, but was arrested for grievous bodily harm and immediately hand cuffed.

By using the words 'I stabbed him' in her call for help, she had inadvertently labelled herself as the attacker.

"I was baffled," she told Brown.

"I was like, hang on I called Triple Zero, I asked for the ambulance, I called for help but I'm being treated as the baddie. No-one's even listening to me… I'm the one being attacked."

Zartarian was rushed to hospital for emergency heart surgery, while police separated Ms Kasparian from her children to record a statement in the garage.

"He grabbed the saucepan and he came at me and he hit me on my head twice and you could see the bends," she told police.

"And that's when I had the knife in my hand and I said just get away from me and he kept coming towards me saying, 'Stab-' - like really with all his heart, like,  'Stab me, stab me, do it, do it'."

"And then he just kept coming into me and he hit me in my, on my face and obviously the knife went into his chest."

She was interviewed again four hours later at the police station and again her story was the same.

The next day, Ms Kasparian’s five-year-old daughter was interviewed by a specially trained female police officer and bravely answered questions on what took place the night before.

Ms Kasparian's barrister, Peter Doyle, says the consistency in each haunting statement is what helped prove she was not a calculating killer.

"They're all consistent with each other that Mark had been intoxicated, that he was being violent and that he’d been assaulting her, and that she acted in self-defence."

Zartarian spent six days in a coma before his life support was switched off.

On the day of his funeral, Ms Kasparian’s charge was upgraded to murder, facing 20 years in prison.

During and after her trial, Ms Kasparian’s story provoked more anger than sympathy with the wider community debating whether she was truly a victim of domestic violence or a murderer.

Her stoic, unshaken appearance at court displaying a high-fashion wardrobe made outsiders question her story.

The media too joined the chorus and dubbed Ms Kasparian as ‘Australia’s Black Widow’, suggesting she had got away with murder.

"Why do you think you were painted in that way?" Brown asked.

"Am I supposed to wail and cry like a crazy person to make people feel sorry for me?" Ms Kasparian answered.

"I'm not gonna behave in a manner that I don't normally. I'm not gonna be someone I'm not just to prove a point."

During the trial it was revealed Ms Kasparian’s neighbours had heard the fight, even saw parts of it and yet none had intervened.

One neighbour described how he watched on from his backyard which overlooked the kitchen.

He told the court he heard Zartarian yell two or three times, "Go on, do it. Be a man". He was so close he said he could see the veins in his neck sticking out.

This again aligned with the consistency in Ms Kasparian's original police statements.

"It corroborated what she was saying," barrister Peter Doyle said.

"When you look at the evidence of different neighbours on their own, it might not have meant anything.

"But when you considered what they were all saying when looking at what she said in her interviews to the police they’re all confirming different aspects of her interview."

Ultimately, Ms Kasparian's self-defence case rested on the size of the stab wound.

In one of the fastest murder trials ever in New South Wales, she was able to prove that she hadn't lost control and thrust the knife into Zartarian's chest.

After just three days of hearings the jury accepted she acted in self-defence and acquitted her of murder.

Although Ms Kasparian cleared her name, retired Supreme Court Judge Anthony Whealy told 60 Minutes this was a case that never should have gone to trial.

"It was really a hopeless crown case," Mr Whealy said.

"Going to trial is expensive, it's time-consuming, it's emotionally horrific for everybody involved. I think in this case it could've been avoided."

"If anyone had just concentrated on the factual elements… they would've seen that it was just a waste of time."

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