A law professor says the solicitor-general referring a major miscarriage-of-justice case to the police raises serious questions about the actions of prosecution lawyers.
But other lawyers warn against reading too much into it, with a lot more work to come before any conclusions are reached.
Solicitor-General Una Jagose has been considering an independent report by Nicolette Levy KC into the actions of Crown lawyers involved in the Alan Hall case.
Hall was convicted of murder in 1986 but his conviction was quashed by the Supreme Court earlier this year, with judges concluding evidence was deliberately altered.
The Court said there was either extreme incompetence or a deliberate, wrongful strategy to achieve a conviction.
Jagose has not released Levy's findings for now, but has asked the police to investigate if charges should be laid relating to aspects of a case during the "1980s".
The actions of all Crown lawyers involved in the case, from 1985 through until 2022, were under scrutiny by Levy.
University of Auckland law professor Mark Henaghan said that the report was being withheld showed how serious it could be.
"There were very serious matters in that Supreme Court decision so it doesn't surprise me that they want to look at it and give the police a chance to respond because there may be sufficiently serious matters that it may lead to prosecutions for some of the behaviour."
Cases like Hall's raised doubts about the fairness of the entire justice system, he said.
"That's really sad to see and it's the kind of thing you'd watch on Netflix and say 'thank God we don't live [there]'.
"Some of the stuff [that came to light in the Supreme Court case] is very off-putting in terms of trusting the system."
But John Billington KC, who has worked as both a prosecutor and defence lawyer, has warned not to read too much into it.
It only showed further investigation was needed, he said.
"We know things have happened [that] should never have happened, and whoever is affected by that is actually entitled to know about it - if there are any criticisms - and to respond.
"And if it leads somewhere else it leads somewhere else.
"But to say it 'will' lead somewhere, or 'may' [lead somewhere] - I'm not sure I'd go that far really."
The way disclosure was done had changed a lot since the 1980s, Billington said. Nowadays everything was handed to the defence which could lead to lawyers being swamped in material - raising its own issues, he said.
Confidence in police
RNZ asked the solicitor-general what assurance she had sought that police could be sufficiently impartial given their own actions were the subject of a number of internal and external probes.
Police also work closely with Crown prosecutors every day.
In a statement, Jagose said Crown Law had confidence in the police.
Billington said there was no other organisation except the police that could do the investigation, and they could be trusted to do it properly.
Highly experienced defence lawyer Marie Dyhrberg KC wanted the police to bring in an independent person to work on the investigation.
Bringing in an outsider would ease any public concerns of bias from police, she said.
She hoped the public would also get to see the full King's Counsel report commissioned by the solicitor-general.
The police and the Independent Police Conduct Authority are conducting their own probes into police actions in the case, with findings expected in the first quarter of next year.
Police said they had received Levy's report.
It would be looked at as part of an already ongoing investigation into the case by Detective Superintendent Graham Pitkethley, police said.
They would make no further comment while that work continued.
Meanwhile, the lawyers' professional body, the Law Society, said it did not comment on any matter before the police.