R v McMahon

In the case of R v McMahon, the Court of Appeal of New Zealand was called upon to determine the admissibility of evidence obtained through an unlawful search of the appellant's residence. Craig McMahon was charged with cultivating cannabis, selling cannabis, possessing cannabis for supply, and possessing equipment capable of being used for cannabis cultivation. The evidence against him was derived from a search conducted under a warrant which the appellant argued was unlawful and unreasonable. The central legal issues were whether the search was unlawful and unreasonable, and if the evidence obtained should be admitted under the balancing test.

The Court found that the search was indeed unlawful. The application for the search warrant contained significant deficiencies, including incorrect and misleading information. For instance, the application inaccurately described the make of McMahon's vehicle and failed to include the dates of his previous convictions. Additionally, the application did not provide reasonable grounds to believe that evidence of cannabis-related activities would be found at McMahon's address. The Court concluded that these deficiencies were serious and could have misled the issuer of the warrant, rendering it unlawful.

Further, the Court determined that the search was unreasonable. Despite the District Court's ruling to the contrary, the Court found that the unlawfulness of the search warranted its characterisation as unreasonable. The Court adopted the approach from R v Maihi and R v Williams, which held that an unlawful search is generally unreasonable unless there are countervailing factors. No such factors were present in this case.

The final issue was whether the evidence obtained should be admitted under the balancing test from R v Shaheed. The Court considered the seriousness of the breach, the nature of the privacy interest, and public interest factors. The unlawful search represented a serious breach of privacy, partly due to police sloppiness. The nature of the privacy interest was significant given it involved a citizen's home. The public interest factors, such as the seriousness of the offence and the quality of the evidence, pointed towards admission of the evidence. However, the Court concluded that exclusion of the evidence was necessary to uphold the rule of law and protect privacy rights. The compelling nature of the evidence and the serious breach of privacy led the Court to rule that the evidence obtained from the unlawful search would be inadmissible at trial.

Therefore, the appeal was allowed, and the evidence obtained as a result of the search of McMahon's address was deemed inadmissible at trial.