The deputy Solicitor General says a rapist's sentence of nine months' home detention is manifestly inadequate and there has been a miscarriage of justice.
An appeal against Jayden Meyer's sentence has been heard in the Rotorua District Court on Tuesday, with victims and their families joined by video link.
Deputy Solicitor- General Madeleine Laracy lodged the appeal last week, submitting that important public interest factors had not been accommodated by the sentencing process.
"The sentence imposed upon Meyer marks such a substantial departure from ordinary sentencing practice that the Solicitor General nevertheless seeks to have it corrected on appeal," she said.
Meyer, who is now 18, raped four 15 year old girls and sexually violated another between 2020 and 2021.
The sentence sparked protests across the country. Laracy told the court a minimum three-year jail sentence should be imposed.
"The sense that the law has miscarried in this case in a way that is favourable to Mr Meyer but arbitrary, inexplicable and ultimately inconsistent with the approach taken to other similarly placed offenders," she said.
The Crown had not sought a prison sentence for Meyer at the time of his trial.
Despite being lodged six weeks late, Laracy said the appeal met the public interest in the open application of criminal justice by providing a transparent and reasoned explanation in how the judge reached an end sentence.
"There is a statutory presumption in the Crimes Act that sexual offending of this nature will be met with a sentence of imprisonment," she said.
She said such an error "risks undermining the rule of law itself, that the law is applied in an even-handed way".
Meyer's defence lawyer Rachael Adams told the court a u-turn now would be cruel and inhuman and that monitored home detention is a suitable punishment.
"The conditions of the home detention sentence are in themselves extensive and onerous and Mr Meyer has complied with them in every respect. It's being monitored, partly in response to the public outcry, monitored by Corrections to the extent of unannounced visits late at night to check his cellphone," Adams said.
"The vilification to which he has been submitted and restrictions on his use of social media means that effectively this young man has been completely isolated."
Both sides recognised the media attention Meyer's sentence had received.
In her submissions, Adams suggested the appeal was a response to such media pressure.
Laracy told the court "any such perception would be wholly wrong".
"In fact, that would be a reason for not appealing because the perception of justice being done free from that type of public pressure is so important and the Solicitor-General and my office is very aware of that."
She said the sentence and the entire approach that has been taken is highly irregular.
In response, Adams said the "extreme public sensationalist reaction" should not be part of the appeal.
"I simply make the point that that's not a driver and should never be.
"If ill-informed public opinion is to the effect that there has been a miscarriage of justice that does not mean that there has been."
The judge has reserved her decision.