Judge Bruce Davidson took Filipo's promising rugby career into account when making his decision at the Wellington District Court, sparking allegations of a "double standard".
A spokeswoman for the Solicitor-General said Crown Law was "looking into the matter".
"We weren't aware of this matter until it appeared in the media over the last 24 hours. We are now looking into the matter and will not be making any further comment about it at this time. "
Family First NZ is amongst those calling for an appeal.
National Director Bob McCroskrie said the sentence was "pathetic" and sent the wrong message to the community.
"This offender-friendly sentence sends a dangerous message and sets a dangerous precedent.
"We simply don't value the protection of victims and the safety of the public - based on the response of our justice system."
This case involved "significant violence towards both males and females", said McCroskrie.
"To be discharged without conviction is insulting and pathetic, and communicates that punishments and consequences will be determined by who you are rather than what you did.
"As a community, we are trying to say that violence is completely unacceptable - yet the sentences given by the courts are completely undermining that message."