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Te Atatu murderer Jaden Lee Stroobant stomped on victim Cunxiu Tian's head before violating her
Jaden Lee Stroobant admits murder of Cunxiu Tian in her Te Atatu home
Killer released from prison just 38 days before murder, violation of pensioner
Today the Crown will seek an indefinite sentence of preventive detention for Stroobant.
He had been out of prison just 38 days when he killed Tian.
In mid-2015 Stroobant was jailed on a raft of charges including burglary.
He was released on December 8, 2015 and lived at a boarding house in Te Atatu.
Shortly before the murder, he moved into a property that bordered Tian's family home.
He was living there with his mother Krissie Stroobant, who spoke to the Herald days after Tian was slain.
She revealed that police had interviewed her for five hours after Tian was killed, quizzing her about her son's whereabouts.
Stroobant initially denied having any involvement in Tian's death and pleaded not guilty to murder and two counts of sexual violation.
However, on the day his High Court trial was set to begin in February, he changed his plea and admitted all three offences.
What is preventive detention?
Preventive detention an indeterminate prison sentence.
Those sentenced to preventive detention may be released on parole but will be managed by Corrections for the rest of their lives.
They can also be recalled to prison at any time should they reoffend.
Under the Sentencing Act 2002 the purpose of preventive detention is to "protect the community from those who pose a significant and ongoing risk to the safety of its members".
The offender must be 18 or older and must be convicted of a qualifying sexual or violent offence.
The court must also be "satisfied that the person is likely to commit another qualifying sexual or violent offence if the person is released at the sentence expiry date".
"The High Court may, on the application of the prosecutor or on its own motion, impose a sentence of preventive detention on the offender," the act states.
"When considering whether to impose a sentence of preventive detention, the court must take into account any pattern of serious offending disclosed by the offender's history; the seriousness of the harm to the community caused by the offending; information indicating a tendency to commit serious offences in future; the absence of, or failure of, efforts by the offender to address the cause or causes of the offending; and the principle that a lengthy determinate sentence is preferable if this provides adequate protection for society."