The mother of the Kahui twins has wiped away tears as she told a coroner's inquest that she did not hurt or beat her sons or cause any injury that resulted in their deaths.
Three-month-old Chris and Cru Kahui died from severe head injuries after being admitted to Auckland's Starship Hospital in June 2006.
Their father, Chris Kahui, was acquitted of the twins' murder in May 2008 after a five-week trial.
Macsyna King proclaimed her innocence several times while giving evidence at a coroner's inquest in Auckland on Tuesday afternoon, breaking down in tears after stating that she never harmed her sons.
She also rejected claims made by her former partner Chris Kahui that their other son Shane, aged 13 months at the time of the twins' deaths, could have caused the injuries after crawling into their nursery.
"I don't believe that Shane could have got up and pulled himself onto the couch, simply because Shane was only learning to hold onto things and stand. Climbing and physically getting himself up onto seats and that sort of thing hadn't yet seen Shane do."
When Coroner Garry Evans asked Ms King about the allegation made during the 2008 High Court trial that the responsibility for the twins' injuries lay with her, she flatly rejected it.
Ms King told the inquest she struggles emotionally a daily basis, knowing there are still allegations that she was somehow involved in the boys' deaths.
Ms King said her former partner's refusal to join his sons at Middlemore Hospital after they were admitted with severe head injuries, made her think he had something to hide.
Senior officer defends investigation
A senior police officer giving evidence earlier rejected accusations by the lawyer for Chris Kahui that he fell below the standard of a competent investigator.
Detective Senior Sergeant Christopher Barry told the inquest on Tuesday he was not aware that Macsyna King had been enrolled in an anger management course the month before the twins' deaths.
Mr Kahui's lawyer, Chris Wilkinson-Smith, asked how police could give a balanced overview of the case without knowledge of this.
However, coroner Garry Evans said Mr Barry had done his very best to present a summary of evidence.
Mr Evans said while the officer may have missed giving plenty of evidence, he is more than capable of going back himself and reading all the relevant documents.
On Monday, Mr Barry said there was no basis to charge Ms King with injuring the twins, given the medical evidence on timing and feeding.
Previously dismissed witness to be called
The coroner is to call as a witness Eru Tuari, who gave evidence for the defence during the 2008 trial , in which the twins' father was acquitted.
At the trial, Mr Tuari said the boys' mother, Macsyna King, had told him that "Chris didn't do it, I did it".
Mr Evans on Monday said he felt Mr Tuari's evidence fell short of the standard of being much help to him.
However, he has changed his mind and has called him to appear before the inquest.
Cost of investigation
The inquest was told on Tuesday police have spent $316,527 investigating the deaths of Chris and Cru Kahui.
Detective Senior Sergeant Barry said police resources were placed under intense pressure immediately after the twins' deaths due to a high number number of other homicides being investigated in the Counties Manukau region.
Though staff levels on the Kahui case were always less than desirable, the investigation was completed competently and expenditure on the investigation was adequate, he said.