The new Evidence Act 2008 introduces new statutory tests for the admissibility of evidence in Victoria.
Section 138 is similar — though not the same as — the test for unlawfully or improperly obtained evidence in Bunning v Cross (1987) 141 CLR 54. Like the High Court’s decision in that case, the new provision requires the trial judge or magistrate to engage in a balancing process when deciding whether to admit the evidence in the exercise of judicial discretion.
138. Exclusion of improperly or illegally obtained evidence
(1) Evidence that was obtained-
(a) improperly or in contravention of an Australian law; or
(b) in consequence of an impropriety or of a contravention of an Australian law-
is not to be admitted unless the desirability of admitting the evidence outweighs the undesirability of admitting evidence that has been obtained in the way in which the evidence was obtained.
The section also provides considerations for excluding or admitting evidence, and provides a couple of circumstances when evidence is automatically considered improperly obtained.
Courts in NSW, the ACT and the Commonwealth have already turned their minds to provisions similar to s 138. In R v Helmhout  NSWCCA 372, the NSW Court of Criminal Appeal considered the effect of non-compliance with regulations mandating the specific entitlements of suspects in custody, and the effect that this should have on the admissibility of the interview subsequently obtained. In that case, investigators failed to notifty the Aboriginal Legal Service that an aboriginal suspect was in their custody, as the regulations required them to.
The trial judge used her discretion to admit the evidence: R v Helmhout  NSWSC 185. The Court of Criminal Appeal ruled unanimously that the decision to receive the evidence was justifiable. (One judge said “plainly correct”.) Key considerations cited were the seriousness of the charge, the inadvertent nature of the oversight, the lack of resulting unfairness to the accused, and the cogency of that evidence.
The onus of demonstrating impropriety or contravention of an Australian law is on the accused, on the balance of probabilities: Robinson v Woolworths  64 NSWLR 612; also DPP v Farr  NSWSC 3. Though those cases rely on the earlier position in NSW law, it was affirmed by the ACT Supreme Court when it considered the current version of s 138: Re Crisp ACTSC 39.
Once this burden has been discharged the prosecution must then satisfy the court it should use its discretion to admit the evidence.