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Domestic-violence murder: Accused describes lifetime of violent abuse, battered women's syndrome
On Monday the Crown told the jury that the fatal incident happened soon after the couple arrived home from a local bar.
They argued, then Ruddelle picked up a 19cm knife and stabbed Ngapera twice, piercing his heart.
Ruddelle does not dispute that she killed the 56-year-old - but denies it was murder.
She says her actions were in self defence - that she was terrified of Ngapera because of years of domestic violence and that he initially lunged at the knife.
The defence claim Ruddelle suffers from battered women's syndrome - now known as social entrapment- and that Ngapera used coercive control over her.
Ruddelle refused to speak to police about the alleged murder, so today in court her story was told for the first time.
She relayed what happened in the lead up to the alleged murder.
The morning before she and Ngapera had visited Work and Income.
While Ruddelle was inside, Ngapera said his car had been stolen and he had been assaulted by three men.
His watch and phone were also taken, he said.
Ruddelle did not believe him, but the pair went to the police station to report the matter.
They went home and to "mellow him out" Ruddelle suggested going to the Crates and Cues bar for a drink.
There the couple consumed beer.
Ruddelle's nephew was a the bar and later agreed to drive the couple home.
Soon after he left, the fatal saga unfolded.
Ngapera had set the dining room table and the pair were talking.
An argument started because Ruddelle's adult son Poutou Cameron had moved in temporarily.
She had not sought "permission" from Ngapera - primarily as it was her home and she felt she did not need to ask about her own children staying.
"Joe set the table….
"Joseph was talking about my children... he was angry at the fact that I didn't tell him that Poutou was coming."
Poutou is Ruddelle's adult son who had moved into her home temporarily.
She had not told Ngapera as she felt she did not need to seek permission in her own home.
Ruddell tried to change the subject and brought up the fact that Ngapera had been assaulted earlier that day.
"I said it was karma that he got a hiding…. Because he had always been violent to me, he was always volatile to me…. I may have provoked him, but that's what I said to him," she explained.
"He was getting angry... there was some yelling going on, it was just back and forth… loud enough to know that I was gonna get a hiding.
"Joseph stood up his chair and came towards me, he didn't like what I said, I knew I was gonna get a crack from him… I knew it was escalating, I knew he was gonna hit me.
"I told him 'stop Joe, stop'.
"And then I yelled out, I never do anything like this but I had to - I yelled out to one of my children… because I needed help."
Ruddelle called out to Cameron - but instead of her adult son, her 14-year-old woke and came running.
The teenager cannot be named for legal reasons.
"He's come in between me and Joe… immediately when he came from the door, in between us," said Ruddelle.
The teen pushed Ngapera against a wall.
"What's going through my mind is that my son has done this… I can only think that Joseph's gonna hurt him, Joseph's gonna smack him - because he was gonna hurt me before (my son came in).
"He had hurt me before…. when he punched me in the head… all those things came back up, about how he could do that to (my son).
"One hard hit could have hurt (my son)... or maybe kill him, that's what my thought was.
"He was gonna hit me like he's hit me before... He was probably gonna hurt me bad or kill me or murder me.
"I'm thinking these things about what could happen to (my son) because no one pushes Joseph like that without him getting angry about it."
Ruddelle said what happened next was fast and instinctive.
"My son's gonna get hurt, Joe's gonna hit him…. My left hand I reached over on the table and I grabbed the knife and I put it in my right hand, pushed (my son) out of the way with my left arm and struck Joe, twice," she said.
"It happened so fast."
Ruddelle said she was not aiming the knife.
Her intention was "just to stop him"
"To stop him from hurting (my son) or myself."
Ngapera fell to the ground.
The teen ran to get Cameron who called 111 and started CPR.
Ruddelle ran next door to get help and returned to the scene.
She was trying to help, touching Ngapera's face and screaming at Cameron to revive him.
"I was getting hysterical… when it happened I went into shock, I just lost my head," she said.
"I didn't understand what I had done… I didn't believe that had been done, that Joseph was lying there... I thought that Joseph would still be alive."
Soon after in the back of a police car Ruddelle was heard saying "thank you Jesus" after police told her Ngapera was dead.
She explained this in court today.
She said she remembered praying as she was in the car with two officers.
"I prayed to the lord to forgive me and to take Joesph into his arms and I loudly said "thank you Jesus"," she said.
"I asked him to forgive me... I felt hurt, I tried to understand what had happened."
Ruddelle explained that in 2017 she had joined the Manurewa Baptist Church and praying was a regular thing for her, usually ending with an audible "thank you Jesus".
Yesterday the court heard that Ruddelle called police 16 times during her relationship with Ngapera, to ask for help when he was being violent, aggressive, threatening or intimidating.
At one point the pair broke up and Ruddelle sought a protection order - but had it discharged two months before Ngapera died.
She told the court today she got rid of the order because she wanted to "grow' her relationship with Ngapera - and he got angry at her for having it in place.
At the beginning of her evidence she spoke about growing up with alcoholic parents in a house where violence was part of daily life.
And she outlined her turbulent and dangerous previous relationships before she turned her mind to Ngapera.
The pair met in 2015 and he was homeless but Ruddelle saw "the good" in him and embarked on a relationship.
It did not take long for the violence to being.
The first time he assaulted her was after a night drinking at home with friends.
"It was early in our relationship ... I don't know if I said anything to provoke him, we were just having a conversation," said Ruddelle.
"All of a sudden he grabbed me by the throat and I was up against the wall and he was strangling me.
"He had me up against the cupboard wall with both of his hands ... I tried to say 'stop Joe this is not you this is not who you are'.
"He had me tight ... he let go and then he grabbed me again by the throat.
"I thought I was going to die."
The trial, before Justice Matthew Palmer and a jury, continues next week.