R v Williams and the Exclusionary Rule: Continuing Issues in the Application and Interpretation of s 30 of the Evidence Act 2006

Abstract

The exclusionary rule -- which gives judges the power to exclude from a criminal trial evidence improperly obtained by the police (or other state actors) -- has undergone significant transformation over the last two decades. Prior to enactment of the New Zealand Bill of Rights Act 1990 (Bill of Rights or the Bill), judges retained a common law discretion to exclude evidence on the grounds of unfairness -- a somewhat murky jurisdiction pegged to various (but not all) instances of police misconduct leading to real or confessional evidence in a criminal case. 1 However, following the enactment of the Bill of Rights, the Court of Appeal quickly fashioned a "prima facie rule of exclusion" for evidence obtained in violation of the Bill's multiple provisions controlling police search and seizure and the investigative handling and questioning of criminal suspects. 2 The prima facie exclusionary rule -- which was jurisprudentially grounded in the imperative to vindicate rights -- existed at common law from 1992 until 2002. 3 However, the rule was itself replaced by the Court of Appeal in the 2002 decision of R v Shaheed. 4 Shaheed substituted for the prima facie rule a "proportionality-balancing test" that created no presumption of inadmissibility for evidence obtained in violation of the Bill of Rights. Focussed on a broad-based notion of the overall interests of justice in a criminal proceeding, the proportionality-balancing test instead asked trial judges to balance a number of different factors to determine whether exclusion ...