There is a difference between a procedural error in steps taken by an enforcement officer which provides a defence to a charge, and an error which results in evidence being improperly obtained: Birchler v Police [2010] NZSC 109 (30 August 2010). An officer had wrongly decided that a breath test could not be carried out at the roadside, and required the suspect to accompany her to the police station for the testing procedures. The accompanying was not voluntary (8). The District Court Judge dismissed the charge, instead of ruling that the improperly obtained evidence was admissible pursuant to the balancing exercise set out in s 30 of the Evidence Act 2006.
In the absence of reasonable compliance with the procedures the defendant had a defence (17). It would have been wrong for the Judge to have proceeded to the balancing exercise, because to do so was "quite inconsistent" with the statutory procedural scheme. The High Court, on an appeal on a question of law, held that the District Court could have undertaken the balancing exercise instead of dismissing the charge. The Supreme Court overruled that and set aside the High Court's order which remitted the case to the District Court for reconsideration.
The Supreme Court took the opportunity to correct a troublesome dictum in R v Gallichan [2009] NZCA 79 at 18, in which the Court of Appeal had indicated that failure to challenge the admissibility of evidence before the close of the prosecution case prevented the issue being raised. That was wrong (Birchler at 21).
