Mateparae appealed his conviction on the basis that he felt errors by his counsel and the trial Judge resulted in a miscarriage of justice.
His lawyer appealed the conviction on three grounds; that Mateparae's trial counsel failed to adequately cross-examine one of the detectives involved; and that the judge ought to have aborted the trial, or given the jury directions, after the trial counsel made "a significant error during her cross-examination of another police officer".
The third ground for appeal was that Mateparae elected not to give evidence in circumstances where he had received inadequate advice from his trial counsel.
Mateparae's lawyer said that these errors resulted in a miscarriage of justice.
However, Justice Graham Lang said he saw "no merit" in all three grounds of appeal and accordingly dismissed the appeal against Mateparae's conviction.