A taekwondo instructor who demanded his students call him 'Master Lion' will die in prison after being sentenced to life without parole for the brutal murder of an entire family, a crime he committed to steal their luxury car.
A Family Betrayed by Their Trusted Teacher
Kwang Hyung Yoo, 51, received his life sentence in the New South Wales Supreme Court on Tuesday for the murders of Min Kyung Cho, 41, her husband Hyun Soo Cho, 39, and their seven-year-old son, known in court as BC. The court heard Yoo, a father-of-two, had been the young boy's taekwondo teacher for years and had encouraged him to take double classes to prepare for a black belt assessment.
On the evening of 19 February 2024, after BC's lessons at the Lion's Taekwondo and Martial Arts Academy in North Parramatta, Yoo lured the boy's mother into a storeroom and strangled her. Her son waited for 90 minutes, eating ice blocks, unaware his mother was dead. Yoo then taught another class before taking the child into the same storeroom and killing him with a pole and an ethernet cable.
Yoo then drove Ms Cho's white BMW X5 to the family home in Baulkham Hills, where he stabbed Mr Cho to death. During the struggle, the husband managed to slash Yoo in the chest, arms, and stomach in self-defence.
The Motive: A Web of Lies and Grandiose Fantasies
The court was told Yoo's motive was shockingly mundane: he wanted the family's BMW. Burdened by financial pressure—$8,584 behind in rent and with $3,202 in credit card debt—Yoo had spun an elaborate lie to his wife. In late January, he falsely claimed the principal of Epping Boys High School had offered him more work and a BMW.
Knowing the Cho family owned the car, Yoo began surveilling their home. CCTV evidence showed him scoping out the Baulkham Hills townhouse on five separate occasions in the weeks before the murders. His web of deceit was part of a pattern; the court heard Yoo was a serial liar who fabricated meetings with mining magnate Gina Rinehart and even falsely claimed he qualified for the Sydney 2000 Olympics.
A court-appointed psychiatrist's report stated Yoo felt that as a 'good person' under financial strain, he was justified in becoming a 'bad person' to give his family what he thought they wanted. He told the psychiatrist there was no motivation for the killings other than to steal the car.
Justice Served: A Life Behind Bars
During sentencing, Justice Ian Harrison noted the 'egregious breach of trust' involved in killing a pupil who looked up to him as 'Master Lion'. He said the family was killed for 'what is, in reality, no reason at all' and that Yoo's risk of reoffending was too high for any lesser sentence.
Despite an early guilty plea and expressions of remorse in a letter where Yoo wrote, 'I know that I have been held captive by sin,' Justice Harrison imposed a life sentence with no parole date, meaning Yoo will die in jail. The judge highlighted that Yoo made no serious attempt to avoid detection, even wearing Ms Cho's Apple Watch, which could have been tracked.
In a victim impact statement, Ms Cho's parents said their hearts were broken, adding: 'We could still hear the screams of [the family] echoing in our ears, as their lives were wrongly taken from them.'
