The NSW government says it will move to block the possible release from jail of triple murderer John Cribb.
Cribb was jailed for three life terms in 1978 for the killings of a Sydney mother and two of her young children.
A spokesman for Attorney-General John Hatzistergos said on Tuesday the government would oppose Cribb's application for a fixed release date, which is to be heard in a Sydney court next week.
"The government will oppose Mr Cribb's application for redetermination on his sentence," the spokesman said.
"... And will also seek orders preventing Mr Cribb from making further applications for a redetermination in the future."
Cribb's application for a sentence redetermination is made possible because he was given the life terms before truth in sentencing reforms were introduced in 1989.
The victims' family, and also the police officer who caught Cribb, have gone public in a call for Cribb to remain in jail for the rest of his life.
"When someone gets three life sentences you think that they're gonna be in jail forever," Gary Connell, whose mother Val was sexually assaulted and then murdered by Cribb, told the Nine Network.
His sister Sally, then aged 10, and brother Damien, four, were also brutally killed.
"My mum was just such a wonderful, wonderful person.
"I can feel nothing, I guess, but despise (sic) for the man."
Former NSW police detective Norm Maroney said Cribb's crimes ranked among the worst in Australia.
"I would describe him as a savagely brutal and merciless human being," Mr Maroney told the Nine Network.
"These murders were probably the worst in NSW or even in Australia.
"None of us could even guess what the family must be going through now."