A Hamilton woman who killed her neighbour with a hammer after leaving a mental health facility will serve at least 10 years in jail.
Christine Morris, 42, was sentenced at the Hamilton High Court on Monday for the murder of Diane White in January 2010.
Morris attacked the 53-year-old two hours after she scaled a fence at the Henry Rongomau Bennett Centre at Waikato Hospital where she was a voluntary patient.
Ms White had been packing her bags to visit her new-born grandchild in Australia at the time of the attack.
Rees Tapsell, the hospital's director of mental health and addiction services, says no one could have predicted the tragedy and staff had acted professionally.
However, Dr Tapsell says an internal investigation has highlighted the need for better training in risk assessment and management, improved observation of at-risk patients and changes to the open ward environment.
Staff contacted police several times to say a patient was missing and had threatened to kill a woman and provided her address.
Gary Chadderton, Diane White's partner of 17 years, was in court for the sentencing on Monday.
Mr Chadderton says Morris had previously threatened Ms White, himself and members of her own family with violence. He says he made numerous calls to police and mental health services, but was ignored.
"They're all covering up their own backsides. It didn't make me feel any better knowing that we warned all these different organisations so many times (that) this woman is unwell, she's psychotic. They took no notice of us."
Mr Chadderton says the sentence is not long enough.
Police were unable to respond to questions on Monday.