FORMER detective and Ninderry MP Dan Purdie has called for mandatory 15-year sentences for "grubs and monsters" who kill children.

Mr Purdie slammed the Legal Affairs Committee's failure to back stronger laws a week after widespread outrage over the jail sentence given to child killer Shane Purssell Akehurst.

A lead investigator on the Akehurst case, Mr Purdie said those who intentionally harmed innocent, vulnerable children like Corby Akehurst deserved to have the book thrown at them.

The LNP's proposed legislation would guarantee child killers received a minimum 15 years' imprisonment for manslaughter and 25 for murder.

"We have got to protect our most vulnerable and deter the monsters from crimes like this," Mr Purdie said.

"Akehurst got more than the average, which is an atrocious six years but it wasn't enough.

"They're failing to support what would be some of the toughest sentences in this country for the murder of innocent, defenceless children."

A spokeswoman for acting Attorney-General Stirling Hinchliffe said Queenslanders rightfully expected the punishment to fit the crime.

"That's why the Palaszczuk government wants to expand the definition of murder so that killers who show callous disregard for children - causing their death - will face life in jail, if convicted," she said.

"The LNP says in the report that they are not opposed to our Bill. We are pleased to have their support."

Bli Bli Neighbourhood Watch president Edith Blanch said members were on average confronted by four domestic violence incidents a week.

Mrs Blanck said she felt "outraged" at Akehurst's sentence, given he could walk free in six years.

"This is about the rights of the community and the rights of victims," Mrs Blanck said.

"We feel outraged at this penalty. "We are objecting the commission's decision."

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