The man who murdered and sexually violated elderly Te Atatu woman Cunxiu Tian was released from prison 38 days before her brutal death.

Jaden Lee Stroobant on Wednesday pleaded guilty to murdering the 69-year-old in her home on January 15 last year.

He also admitted two charges of sexually violating the pensioner, whose body was found by her daughter.

The Herald can now report that Stroobant was released from prison just over a month before the brutal attack.

In mid-2015 Stroobant was jailed on a raft of charges including burglary. He was released on December 8, 2015.

He spent time living at a boarding house in Te Atatu but shortly before the murder, moved into a property that bordered Tian's family home.

He was living there with his mother, 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 Stroobant's whereabouts.

Stroobant initially denied having any involvement in Tian's death and after he was charged with murder and two counts of sexual violation, he pleaded not guilty

However this week, on the day his High Court trial was set to begin, he changed his plea and admitted all three offences.

Justice Graham Lang then released the police summary of facts to the Herald, which outlined how Stroobant attacked Tian, stomping on her head and inflicting a fatal injury, before subjecting her to a brutal sexual attack as she lay dying.

The summary also revealed for the first time that Stroobant tried to evade police after the murder, hiding in the boot of his girlfriend's car at one stage.

The specific details of the sexual attack are suppressed - an order that will be revisited at sentencing and will be strenuously opposed by the Crown, Tian's family and the Herald - but it was revealed that Stroobant's semen was found on the elderly woman's underwear.

Stroobant will be sentenced on March 13.

Crown prosecutor Jo Murdoch said a sentence of preventive detention - an indefinite term of imprisonment - would be sought.

Stroobant's lawyer Emma Priest would attempt to keep details of the sexual offending suppressed permanently in a bid to protect her client in prison.

Stroobant is in segregation and, according to Priest, fears that if details of his sex attack on Tian are published his safety could be compromised.