Blessie Gotingco's husband Antonio says he is "disappointed and devastated" that the inquiry into his wife's murder found no one but her killer was to blame.
Corrections has been cleared of any blame in the death of Mrs Gotingco, who was killed by a man who had been released from prison.
Tony Robertson was out on special release conditions, after serving eight years in jail for convictions relating to abduction, indecent assault and attempted kidnapping of children, when he ran over, raped, then murdered the Auckland mother of three in 2014.
Last year, Robertson was sentenced to at least 24 years in jail.
The inquiry report into the management of Robertson was released today by Justice Minister Amy Adams and Corrections Minister Judith Collins.
Ms Collins said Mrs Gotingco's family has been fully briefed on the report's contents, conclusions and recommendations.
But at a press conference held this afternoon, the family said they were disappointed with the decision.
Mr Gotingco read a statement, saying it was the ineptitude of Corrections which led to her death.
"It is glaringly obvious to us and the wider public that they do not have the capability to manage these high risk sex offenders.
"In fact, I think the offenders manage them."
Family spokesperson Ruth Money said the family wanted to know, if Robertson was being monitored, how it was possible for him do what he did.
"We assume quite wrongly that that person - every move was being watched, every breach or signal or escalation was being managed so that they would not and did not act in the way that they ended up acting in.
"And that's where Antonio's heart bleeds the most, he wanted to prevent this happening again and he does not believe that that report is going to do that."
Mr Gotingco said the family would now regroup and consider what steps it would take.
Mel Smith, CNZM, who conducted the inquiry concluded: "I have not found that any failings or deficiencies in systems or practices in the management of Robertson following his release from prison, provided any opportunity for the murder of Mrs Gotingco.
"The information obtained by the inquiry compels me to the view that Robertson, and only Robertson, can be held responsible for what happened to Mrs Gotingco. That was the outcome of the trial when Robertson was charged with rape and murder, found guilty of both crimes and sentenced to life imprisonment."
However, the report suggested a raft of potential changes to the way dangerous criminals are dealt with.
It identified 27 recommendations which identify areas where the management of high risk offenders could be improved.
Corrections Chief executive Ray Smith said changes had been suggested as a result of Mel Smith's review.
He said in future more people would be involved in making decisions such as those made in Robertson's case.
"The primary risk that's seeking to be avoided by notifying neighbours when there's a sex offender in the community ... generally we're concerned about their behaviours for grooming young children."
Mr Smith said "very, very sadly" notifying neighbours in this case would not have made a difference because the offence was not with a child and did not happen in the street where Robertson lived.
Ms Collins said there was nothing that could have stopped Robertson, even after he served the full eight years in prison.
"He'd served the full term of his sentence, he did not undertake any rehabilitation in prison, and in fact, actively tried not to. He has never accepted responsibility for any of his offending, and he is just an incorrigible case and nothing would have made a scrap of difference."
Ms Collins said some people should never be released from prison and Robertson was one of them.