The windows were up on the vehicle but the doors were unlocked and a hose was running from a generator to tubing that went through the tailgate and was attached with tape.

Clothing had been pushed into other gaps around the vehicle.

Det Coady said letters were found written by Mr Poxon to his mother and Ms Bell.

Sgt Norton asked whether the letters contained words along the lines of those commonly found in suicide notes, which Det Coady confirmed.

He also said a digital camera had been found containing a voice message saying in part “I can’t live without my children and they can’t live without me”.

In answer to a question from Sgt Norton, Det Coady said the last known contact from Mr Poxon was five days earlier and that he had formed the opinion that Mr Poxon had put Bon in the baby seat, convinced Jack and Maddie to stay in the car while he had connected the hose and killed his children and himself with carbon monoxide poisoning.

Det Coady said as far as he knew there was no prior indication of self-harm from Mr Poxon, nor that he would hurt his children.

But, he said, Mr Poxon had earlier faced a domestic violence charge, had an Apprehended Violence Order made against him and was perhaps frightened that he could go to jail as Ms Bell had again reported an incident.

An emotional Ms Bell made a statement when invited by Mr Dillon.

In it she said that “what Gary did was selfish, cowardly and there was no way anyone could have known”.

“I thought he would kill me but never the children,” she said.

“When I was asked if I thought they’d be safe I said ‘yes’, I didn’t think he would do anything to harm his children.”

But most of all, Ms Bell wanted to bring to the attention of government the laws around victims of domestic violence.

She said that because she was the one who left the home, she had no right to go back and remove her children.

“The laws around that need to be addressed,” she said.

“When people leave the home because of domestic violence, they can’t take the children so it is just easier to go back.

“If (my children) had been removed they would still be alive today.

“Women stay in violent relationships because they have no other choice (and) I hope this can save someone else’s children.”

In a poignant summing up Mr Dillon said “there are things that go beyond the law”.

“The death of children in horrible circumstances such as this raises concerns about the human condition,” he said.

“These stories affect anyone with children and they go to the mystery of the human heart.

“How anyone bears the sorrow of losing three children I don’t know.”

Noting Ms Bell’s pregnancy Mr Dillon said it was “good to see the pain you have been through hasn’t destroyed your love of life”.

Outlining the evidence, Mr Dillon said the children had been sedated before being gassed and the bodies had been in the car for some four days before being discovered.

The questions as to why Mr Poxon did what he did and what “tipped him over the edge”, he said, were unanswerable. He appeared to love his children and would not harm them but he was frightened of going to jail and blamed Ms Bell for all his problems.

Mr Dillon said Mr Poxon was in a “distorted state of mind” but “that was not to excuse it”.

Speaking to Ms Bell about her statement, he said he had difficulty in “framing a recommendation” but would “take your cry for help” to the Attorney General and ask that he consider it closely as there were points in it that needed to be looked at.

Again to Ms Bell he said: “I hope your life will be long and fruitful and that the lives of your children will be a comfort to you.”

Mr Dillon gave his official findings that were: “Mr Poxon died as a result of self-inflicted carbon dioxide poisoning” and the three children “died as a result of carbon dioxide poisoning inflicted on them by a known person”.