“We believe he preferred to go to prison rather than return to his hometown,” the statement said.
Mr Yu and Ms He claimed Dong had told their daughter in the lead-up to her death that the Immigration Department had cancelled his student visa, and they believe “he was afraid that our daughter would report his illegal immigration status, and feared being repatriated to China”.
“He learned from the internet that there was no death penalty in Australia, so he decided to do premeditated murder.”
According to documents submitted by the Crown, Ms Yu had told her mother that Dong planned to move out on June 9, and she had refunded him two weeks’ rent without argument.
On June 8, Ms Yu told her mother the power had gone out. It would be their last communication.
Agreed facts state that, two days before the murder, Dong did a number of online searches, including “How would Homicide be sentenced in Australia” and “comparison of underage criminal offence sanction between China and Australia”.
He also made more than a dozen searches of different areas around Sydney, including Royal National Park, St Ives, St Ives Chase, Mount Colah and Berowra.
A psychiatric assessment of Dong tendered to the court, which concluded that he suffered from schizophrenia, also stated he was worried that Ms Yu would report him to the Immigration Department.
While their daughter was missing, Mr Yu and Ms He travelled to Australia from China and made anguished public pleas for help to find her.
In the impact statement, Mr Yu said the family had been “ruined by this murderous offender” and that his wife had “reached the edge of collapse”.
“She washes her face with tears every day, and wakes up in nightmares almost every day. She wants to end her life every day and follow our daughter.
“In order to dissuade and prevent her from doing wrong things, her body and mine are already blue, purple and bruised. I can’t leave her on her own at any time,” he said.
“Our daughter had tried her best and worked hard in Australia for ten years, building her dream step by step,” the statement said.
“She would have been a productive, positive and excellent part of the Australian community. Such brilliant achievements and a bright future have been destroyed by this offender. My wife’s life and mine destroyed too.”
Noting Dong’s health records referred to past symptoms “regarded to be factitious or malingered”, Crown prosecutor Gareth Harrison sought an adjournment in order to seek a second psychiatric assessment, which acting Justice Peter Hidden granted.
The sentencing hearing is set to resume on August 7.
❏ Support is available for those who may be distressed by phoning Lifeline 13 11 14; Mensline 1300 789 978; Kids Helpline 1800 551 800; beyondblue 1300 224 636; Men’s Referral Service 1300 766 491.
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Jenny Noyes is a journalist at the Sydney Morning Herald.