Police lawyer Sally Carter appeals Filipo's discharge without conviction in the High Court at Wellington on Wednesday.

Losi Filipo's assault case could go back to court after a judge overturned the Wellington rugby player's discharge without conviction.

Justice David Collins, in the High Court at Wellington, found in a judgment published on Thursday afternoon that district court judge Bruce Davidson made errors in 18-year-old Filipo's sentencing on assault charges.

Police appealed against Davidson's ruling, with police lawyer Sally Carter argued that Davidson "glossed over" the scale of the violence involved when Filipo attacked four people, including two women, on a night out in Wellington.

MONIQUE FORD/STUFF Justice David Collins, pictured, ruled district court judge Bruce Davidson made errors in Filipo's sentencing.

Collins' judgment centred on three errors by Davidson.

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They were Filipo's role as instigator of the violence; the fact he stomped on victim Gregory Morgan's head four times, including at least once when he was unconscious and vulnerable; and that Davidson erred in his judgment of the seriousness of the consequences of a conviction.

Filipo pleaded guilty to the assault of four people in Wellington last October.

Filipo pleaded guilty to the assault charges after it was indicated to him that, if he did so, he would receive a discharge without conviction.

He will now be given the opportunity to vacate his guilty plea, meaning the case would go back to court for trial.

Collins found that, although Davidson recorded that Filipo stomped on Morgan on about four occasions, he did not refer to the fact that the stomps were to Morgan's head and that he was already unconscious, which made the offences particularly serious.

GETTY IMAGES Filipo in action for a Wellington XV side against the Cantabrians at Rugby Park, Christchurch, earlier this year.

"This is the most disturbing aspect of Losi Filipo's behaviour. It was potentially lethal conduct and required specific consideration."

The evidence was that a conviction would make obtaining a professional rugby contract "much harder", but that was not the same as a "real and appreciable risk" that Filipo would not get a professional rugby contract if convicted, Collins wote.

It was not ruled out, and neither was a rugby career overseas, Collins found.

The judgment noted that, at the time of offending, Filipo, from Waitangirua, a disadvantaged area of Porirua, was 17 and attending St Patrick's College in Silverstream, Upper Hutt.

He had been placed there because of the efforts of a voluntary youth worker who recognised his potential. He had struggled academically at school, but was an exceptional rugby player.

Filipo was also doing teacher aide work voluntarily at a school for at-risk youth, volunteering at a sports trust. After the assaults, he picked up a part-time job grooming cars to repay $1000 in reparations to his victims.

Collins wrote that Filipo was entitled to sentencing credit for his youth, remorse and conduct after the assault.

"When these factors are weighed in the balance, it is easy to understand why Judge Davidson took the compassionate approach that he did.

"As I have stressed, however, Judge Davidson erred by not taking into account relevant matters. As a result, he under-assessed the gravity of Losi Filipo's offending."



The judgment also revealed police did not carry out an initial request from the victims to appeal against the discharge without conviction.



The national manager of the police prosecution service filed an affidavit in which he explained the victims had notified police that they believed an appeal should be filed, because the "factual basis of the sentencing was inaccurate".

However, it was concluded at the time that this did not meet the threshold for an appeal.

Police explained that, either through "oversight or miscommunication within the police prosecution service", Filipo's case was not referred to the solicitor-general "when it should have been".