Crown Law in Wellington has filed an appeal against the sentence, concerned that Justice Helen Cull's starting point for determining the penalty was manifestly inadequate, and that there should have been a minimum non-parole period, equivalent to at least half the end sentence.
The defence also filed an appeal this week, based on legal aspects of the trial and judge's directions and decisions about the admissibility of some evidence.
Radio New Zealand reported a brief statement from Crown Law confirming its position: "The Crown has filed an appeal against the sentence imposed on Mr Matamata. The Crown challenges both the length of the sentence as manifestly inadequate and the absence of a minimum period of imprisonment," Crown Law said.
High-profile veteran and semi-retired Napier barrister Russell Fairbrother QC, who is not involved in the case but who in addition to his legal career had several roles in legal matters during six years a Member of Parliament, including chairing a committee to review the Evidence Act, said it was "inevitable" there would be appeals given the historic nature of the prosecution.
No one had previously been prosecuted in New Zealand for a combination of slavery and people trafficking offences, and Fairbrother said there were "areas" of the law that had not been explored before.
Legal sources had told Hawke's Bay Today before the trial that appeals would be likely almost whatever the outcome, to get the matter before the higher authority of the multiple judges of the Court of Appeal.
In relation to the defence appeal, Fairbrother said that as Matamata had denied the charges and gave evidence in court maintaining his stance he would "clearly" have been dissatisfied with the outcome, and likewise it was inevitable that the outcome would be challenged.
The Crown is appealing his 11-year sentence, saying it's "manifestly inadequate".
Detective Inspector Mike Foster previously acknowledged the victims, saying it was "incredibly brave to come forward and give evidence against a matai, a chief, they did an incredible job".
He said victims were emotionally and physically abused and "went through a pretty awful ordeal".
At the trial, Justice Cull said the victim impact statements from the 13 victims showed a thread of cultural shame over not being paid and being unable to return money to Samoa for their families, and being unable now to return to New Zealand because of their immigration status.
Crown prosecutor Clayton Walker sought a sentence of 15-16 years. Defence counsel Roger Philip suggested a starting point of 13-14 years, with a two-year discount to reflect the forfeiture and reparation.