The case of convicted child molester Peter Ellis is "the biggest miscarriage of justice in this country," opposition leader Simon Bridges says.
"When you look at it, you see irregularities in terms of the investigation, you see some strange allegations being made and you also see something like the sense of a witch-hunt," Mr Bridges said.
Mr Ellis was found guilty of 16 sexual offences and sentenced to 10 years in jail in 1993.
He maintains his innocence.
Lawyer Nigel Hampton QC says the case is "a festering ulcer on the face of New Zealand justice".
"It's continuing and it shouldn't be there. It's almost 30 years now, for goodness sake," he said.
In 2015, the then National government rejected a request for a commission of inquiry into the case - and Mr Bridges says he still believes it's not needed.
However, Mr Hampton disagrees, saying Mr Ellis' case is the sort which needs to be taken to a criminal cases review commission.
"He hasn't got a white knight with deep pockets that can keep funding things. There are volunteers trying to work on his case," Mr Hampton said.
Justice Minister Andrew Little agrees, saying, "It's not good enough just to say there's been this massive miscarriage [of justice] and nothing should be done about it".
"That is the reason why we are setting up a criminal cases review commission," Mr Little said.
The commission would review cases and send them back to court if it finds concerns about the verdict, and Mr Little hopes to have a bill before Parliament by the end of the year - and passed by the middle of next year.
"We have to have safety valves to make sure that people, in the end, do get justice or the closest thing to it," Mr Little said.
Mr Bridges said: "I don't think we need another quango. I think, actually, anything a quango can do, we already, in New Zealand, have the powers to do."
But Mr Hampton said he "can think of three or four [cases] outside of Ellis that I'm looking at at the present time, wearing another hat."
For those people, and Mr Ellis, a commission can't come fast enough.