Where irregularities in the course of a trial in New Zealand were not so grave as to undermine the integrity of the trial in such a way that the accused was denied a fair trial, the proviso in the Crimes Act 1961(New Zealand) s.385(1) could be invoked, allowing the court to dismiss an appeal against conviction on the ground that no substantial miscarriage of justice in fact occurred.

[2005] UKPC 30