Australia woman stabs 14-year-old daughter's boyfriend with kitchen knife, claims she thought he was intruder

A mother who found her daughter's boyfriend semi-naked in a bedroom stabbed him with a kitchen knife.

The Australian Broadcasting Corporation (ABC) reported the incident took place in the family's suburban Perth home in 2023.

Jennifer Mui Len Chin was found guilty of stabbing her daughter's boyfriend, 14, in her Parkwood home.

How the attack unfolded

On the evening of the attack, Chin's daughter snuck her boyfriend into the house and had sex with him in her father's bedroom.

On the same night, Chin was suspicious when she saw the door of her husband's bedroom closed. She forced her way past her daughter, 14, to open the door and found her boyfriend bare chested under the covers of the bed.

Thinking he might be fully naked, she tried to pull the covers off him while asking him who he was.

According to ABC, the boy said "I'm sorry" while the girl claimed she was trying to help the boy who was homeless.

However, Chin was convinced he was an intruder and in order to "protect my kids", she told her six-year-old son to get a knife from her kitchen.

She then stabbed the teen twice in the chest. The teen suffered wounds to the left and right of his chest. He also suffered more superficial cuts on his back near his shoulders. 

Mother's beliefs

Chin's daughter warned her before she stabbed her boyfriend that she would go to jail for doing this.

Chin responded: "I don't care, he's an intruder."

She did not want her daughter to have a boyfriend at her age and told the court that she did not believe in sex before marriage.

Self-defence claim rejected

Her lawyer Mark Andrews spoke of the dread Chin must have felt upon seeing the bare chested teen in her room, not knowing if her daughter was in the bedroom "under threat, force or coercion".

Chin also told the court that she just wanted the teen to stay away from her and her kids.

However, the prosecutor, Chadd Graham, did not accept Chin's self-defence claim. He added that there were no grounds to believe he was a home invader who presented a threat.

Graham added that while Chin relied on the home invader defence, the use of violence by Chin was unlawful because she did not have objective, reasonable grounds to think the teen was a home invader. 

On top of that, Graham said the teen had said "sorry" more than 10 times upon being discovered by Chin and was trying to escape when he went to the locked front door.

Six-year-old son speaks

According to ABC, Chin's six-year-old son said during his police interview that his "mum trapped him and stabbed him" and then "they ran away". The boy was referring to his sister, who had joined her boyfriend in fleeing the house.

He added that his mother asked him to get a knife from the kitchen.

He did not witness the actual stabbing but heard his mother say to the teen "you have nowhere to go, now".

Graham said this proves Chin was the aggressor, not the teen.

Secret boyfriend traumatised

The victim's father described the incident as a "nightmare" for his son, saying his son would carry both physical scars as well as the "trauma" through his life.

The judge said that while she did not think Chin was at risk of reoffending, it was a very serious offence and the state may ask for a term of imprisonment.

Chin will return to court on Sep. 3 for sentencing.

Top photos via Australian media and Canva