The House of Lords held that the fact that the accused was induced to commit the offense by the police or an agent provocateur was never a ground for excluding relevant and admissible evidence of the offense. In New Zealand, however, unfairly obtained evidence can be excluded on the grounds of entrapment. Furthermore, the general restriction of the scope of judicial discretion is unsatisfactory since it results in arbitrary distinctions and is based on an excessively narrow view of the functions of a trial judge, which assumes that those functions pertain only to ensuring fairness of a trial process. A different approach was adopted by courts in Scotland, Ireland, and Australia, where the desirability of convicting the guilty would not excuse judges' broad discretion in weighing two conflicting issues: the public need to bring to conviction those who committed criminal offenses and the protection of the individual from unlawful and unfair treatment. In practice, although the desirability of convicting the guilty does not excuse every transgression in the course of crime detection, a minor or 'technical' illegality would not lead to exclusion. This approach, superior to that approved by the House of Lords, is also consistent with the New Zealand tradition and, thus, should be adopted. Footnotes are included.