Teen killer's to-do list before bashing mum and two siblings to death

One of Australia’s most notorious child killers is set to be released, more than two decades after being convicted of brutally murdering his mother and two siblings.

Matthew Wayne De Gruchy was just 18 when he bludgeoned to death his mother, sister and brother in their Illawarra home in March 1996.

Police believed the murders were likely carried out with a tyre lever or jack handle, although no murder weapon was ever recovered.

De Gruchy has always denied being responsible for the brutal deaths, insisting he was with his girlfriend and found the bodies when he returned home.

While the case against him was circumstantial, De Gruchy was jailed for at least 21 years in 1998 for murdering his mother Jennifer, 42, brother Adrian, 15, and sister Sarah, 13.

A handwritten note by De Gruchy was used in the trial to link him to the murders.

It appeared to be a scribbled to-do list which included lines such as “throw bottle down the back", "cut somewhere with knife", "hit arm with pole", "have shower", "Sarah, Mum, Adrian".

The damning note was found in a bag dumped in a dam near his girlfriend's house.

Matthew De Gruchy is escorted from the Wollongong Court cells in December 1996. Source: Kirk Gilmour via Getty Images

NSW Justice Michael Grove said the attack involved "brutality that beggars description".

Now, at age 41, De Gruchy is set to be released next month.

The NSW State Parole Authority on Friday granted the convicted killer parole under numerous conditions, including that he participate in psychological counselling and not contact his victims' family – except for his father and any paternal relation.

Former detective Belinda Neil – who medically retired from the NSW police due to PTSD – detailed the horrific crime in her 2014 book Under Siege.

It was the first homicide crime scene she had attended in her career and it left an indelible mark on her.

“You couldn’t fathom the amount of damage that had been done to these people. The amount of anger that must’ve been involved in this particular attack,” she told the Australian True Crime podcast last month.

Ms Neil described the then 18-year-old De Gruchy as a “slight and insipid-looking boy” and was astonished at the brutality he was was alleged to have caused.

“When I saw the ferocity of how these people were attacked, putting those two things together was very difficult,” she recalled.

Wayne De Gruchy, father of Matthew, leaves the Supreme Court, 3 July 1996. Source: Jim Rice via Getty Images

In a statement announcing his release, the NSW State Parole Authority said it believed any risks of granting parole could be appropriately managed.

"In making its decision, the authority considered advice from the Serious Offenders Review Council and Community Corrections that release to parole was appropriate and any risks could be appropriately managed in the community," it said.

De Gruchy is scheduled to be released from custody in mid-August.

He'll remain on parole until his maximum 28-year sentence expires in June 2024.

With AAP

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