Wellington Rugby and Losi Filipo have agreed to terminate his contract after the player was discharged without conviction for an attack on four people.
Mr Filipo, who was 17 at the time, had been charged with assaulting two men and two women in central Wellington last October.
He was discharged without conviction last month.
That decision, and Wellington Rugby's decision to support Mr Filipo after the attack, have led to accusations that he escaped conviction because of his promising rugby career.
A victim of the attack had called for him to be dropped from his team.
The Solicitor-General has been looking into the judge's decision to discharge Mr Filipo.
Crown Law was not aware of the matter until the story appeared in the media over the past 24 hours, a spokesperson for the Solicitor-General said.
"All we can say at this point is that we are now looking into this matter and will not be making any further comment at this time."
Wellington Rugby said in a statement this evening that Mr Filipo had withdrawn himself from the Wellington Lions 2016 Mitre 10 Cup squad.
It said Mr Filipo hoped that would go some way to help the victims move on with their lives.
"I understand why the victims of the assault do not want to talk to me and have not taken up an offer of restorative justice, but I would like to publicly apologise for my actions and the damage they caused.
"I made a huge mistake that my victims and myself will have to live with for the rest of our lives."
Wellington Rugby chief executive Steve Rogers said it was an unfortunate situation for everybody involved.
"Our first thoughts are with the victims of this assault. Wellington Rugby would like to extend our sympathies to the two men and women involved in the incident and reiterate the fact that we do not condone violence in any form."
Mr Rogers said the organisation wanted to support Greg Morgan, one of the victims of the attack, who was punched and had his head stomped on repeatedly.
"We would like to extend an offer of assistance and support to Greg Morgan, a member of our rugby community who we have learned will not be able to play the game due to his injuries."
Wellington Rugby was not washing its hands of Mr Filipo, and it would continue to offer support to him, Mr Rogers said.
"Wellington Rugby believes the best outcome for society would be for Losi to remain involved in the game of rugby. To that end we put support structures in place which we believe have already helped him make big advancements."
Speaking at a news conference this evening, Mr Rogers said Mr Filipo had come forward with the proposal to end the contract.
"Losi came forward and said 'I'd like to go down this track'."
A lot of the information that had come out in the past day was new to Wellington Rugby, including the judge's summation in Mr Filipo's court case, he said.
It hadn't been involved in the court case and had only provided information about what would happen if a professional rugby player were to receive a conviction, Mr Rogers said.
Read the judge's sentencing indication:
The judge had said that rugby could play a big part in Mr Filipo's rehabilitation, and the organisation trusted the judicial system, he said.
Mr Filipo had completed 150 hours of voluntary work with a youth development group, promoting positive behaviour through sport.
Former judge criticises sentence
Retired district court judge Roy Wade earlier told Checkpoint with John Campbell Mr Filipo should never have been discharged without conviction.
"How on earth do you get down from (an) 18-month imprisonment to no penalty at all?" - Roy Wade
Someone being good at sport should not be a factor in deciding their sentence, he said.
"I don't care what the consequences of entering a conviction would be, whether it ruins his career or not as a sportsperson, it's simply too serious.
"I may be good at tiddlywinks. Does that mean I should get a lesser sentence than somebody who isn't?"
Mr Wade acknowledged that loss of career potential due to a conviction was greater for some than others.
"But on the other side of the coin is that you know, if you're a world tiddlywinks champion, that your moneymaking activities are on the line if you step out of line and commit an offence."
Mr Wade said the section of law allowing people to be discharged without conviction was intended for minor crimes - those that would generate a fine or community service - and not those with a starting point of imprisonment.
"I think Parliament ought to look at it again and make it much more restrictive," he said.
"How on earth do you get down from [an] 18-month imprisonment to no penalty at all?"