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.
(2) Without limiting subsection (1), evidence of an admission that was made during or in consequence of questioning, and evidence obtained in consequence of the admission, is taken to have been obtained improperly if the person conducting the questioning—
(a) did, or omitted to do, an act in the course of the questioning even though he or she knew or ought reasonably to have known that the act or omission was likely to impair substantially the ability of the person being questioned to respond rationally to the questioning; or
(b) made a false statement in the course of the questioning even though he or she knew or ought reasonably to have known that the statement was false and that making the false statement was likely to cause the person who was being questioned to make an admission.
(3) Without limiting the matters that the court may take into account under subsection (1), it is to take into account—
(a) the probative value of the evidence; and
(b) the importance of the evidence in the proceeding; and
(c) the nature of the relevant offence, cause of action or defence and the nature of the subject-matter of the proceeding; and
(d) the gravity of the impropriety or contravention; and
(e) whether the impropriety or contravention was deliberate or reckless; and
(f) whether the impropriety or contravention was contrary to or inconsistent with a right of a person recognised by the International Covenant on Civil and Political Rights; and
(g) whether any other proceeding (whether or not in a court) has been or is likely to be taken in relation to the impropriety or contravention; and
(h) the difficulty (if any) of obtaining the evidence without impropriety or contravention of an Australian law.
The International Covenant on Civil and Political Rights is set out in Schedule 2 to the Human Rights and Equal Opportunity Commission Act 1986 of the Commonwealth.
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Continuity and change – major change
Exclusion of illegally or improperly obtained evidence
The desirability of admitting evidence recognises the public interest in all relevant evidence being before the fact-finding tribunal. The undesirability of admitting evidence recognises the public interest in not giving curial approval, or encouragement, to illegally or improperly obtaining evidence generally (Kadir & Grech v The Queen  HCA 1, ).
Onus and burden of proof
The party seeking to exclude the evidence has the burden of showing that the conditions for its exclusion are satisfied, namely that it was obtained improperly or in contravention of an Australian law. The burden then falls upon the party seeking the admission of the evidence to persuade the court that it should be admitted. There is thus a two stage process. The party seeking admission of the evidence has the burden of proof of facts relevant to matters weighing in favour of admission. It also has the burden of persuading the court that the desirability of admitting the evidence outweighs the undesirability of admitting evidence obtained in the way in which it was obtained (at ).
policy considerations supporting the non-admission of the evidence suggest that, once the misconduct is established, the burden should rest on the prosecution to persuade the court that the evidence should be admitted. After all, the evidence has been procured in breach of the law or some established standard of conduct. Those who infringe the law should be required to justify their actions and thus bear the onus of persuading the judge not to exclude the evidence so obtained (ALRC 26:1 at ).
‘evidence that was obtained … improperly or [unlawfully] or, … in consequence of impropriety or an [illegality]’
(i) Causal connection
is at least arguable that the formulation ‘obtained in contravention’ should be construed so as to encompass the entirety of an integrated scheme, particularly a scheme designed to protect fundamental freedoms. The formulation ‘obtained improperly’, not presently relied upon, may well be even broader (at -).
(ii) 'Improperly or in contravention'
[n]ot every defect, inadequacy, or failing in an investigation should result in a finding that the section applies merely because it may be considered that, as a result of those defects, inadequacies or failings, the investigation was not properly conducted or that the police did not act properly in a particular respect. On the other hand, the terms of s138(3)(e) … make it clear that the conduct need not necessarily be wilful or committed in bad faith or as an abuse of power’ (R v Cornell (2003) 57 NSWLR 82;  NSWSC 97 at ).
(iii) Illegal conduct
‘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 the evidence was obtained’
Subsection 138(2): Admissions
(ii) 'False statement'
would be strange to conclude that an investigative technique of a kind that has received the specific approval of the High Court should be characterised as 'improper' merely because it involves the use of a legitimate deception on the part of the police (R v Weaven (Ruling No 1)  VSC 442 at ).
Subsection 138(3): Matters the court must take into account
(i) Weighing the factors
[N]o preponderance is ascribed to any of the matters identified … over others; each, if applicable, is to be weighed in the balance in favour of or against the exercise of the discretion (ASIC v Macdonald (No 5)  NSWSC 1169 at  per Gzell J; see also Matthews v SPI Electricity Pty Ltd & Ors (Ruling No 31) (2013) 42 VR 513;  VSC 575 at  per J Forrest J).
(ii) ‘the probative value of the evidence’: s138(3)(a)
[e]xclusion of an item of evidence is more likely to endanger accurate fact finding if the evidence is highly probative than if it is of minimal relevance (ALRC 26:1 at ).
it is not enough for a court merely to form an impression of the probative value … there must be a systematic analysis of the impugned body of evidence sufficient to reach at least a preliminary view as to its “quality and frailties”. However, this assessment must necessarily take place within the limits imposed by the nature of the evidence and the time at which the application is made (Matthews v SPI Electricity Pty Ltd & Ors (Ruling No 31) (2013) 42 VR 513;  VSC 575 at  per J Forrest J).
(iii) ‘the importance of the evidence in the proceeding’: s138(3)(b)
(iv) ‘the nature of the relevant offence, cause of action or defence … and the proceeding’: s138(3)(c)
(v) ‘the gravity of the impropriety or contravention’: s138(3)(d)
the more egregious the illegality or the impropriety accompanying the obtaining of the evidence, the more likely it is that the balance will fall in favour of the exclusion of the evidence (R v Gilham  NSWSC 88 at ).
At the least serious end of the spectrum of improper conduct would be that which did not involve any knowledge or realisation that the conduct was illegal and where no advantage or benefit was gained as a consequence of that impropriety. In the middle of the range would be conduct which was known to be improper but which was not undertaken for the purpose of gaining any advantage or benefit that would not have been obtained had the conduct been legal. At the most serious end of the range would be conduct which was known to be illegal and which was pursued for the purpose of obtaining a benefit or advantage that could not be obtained by lawful conduct (DPP v Marijancevic (2011) 33 VR 440;  VSCA 335 at ; cited with approval in Matthews v SPI Electricity Pty Ltd & Ors (Ruling No 31) (2013) 42 VR 513;  VSC 575 at  per J Forrest J).
(vi) ‘whether the impropriety or contravention was deliberate or reckless’: s138(3)(e)
Conduct would be reckless if the officer had foresight that it might be illegal but proceeded with indifference as to whether that was so. What is described as an alternative of a ‘don’t care’ attitude expressed in ... Helmhout must be understood as meaning that the offender, recognising that the conduct might be illegal, did not care whether it was (DPP v Marijancevic (2011) 33 VR 440;  VSCA 355 at ).
(vii) ‘whether the impropriety or contravention was contrary to or inconsistent with.. the International Covenant on Civil and Political Rights’: s138(3)(f)
(viii) ‘whether any other proceeding… has been or is likely to be taken in relation to the impropriety or contravention’: s138(3)(g)
[t]he availability of alternatives to evidentiary exclusion should be an important factor in the exercise of the judicial discretion … [including] civil actions, criminal prosecutions and internal and external disciplinary procedures (ALRC 26:1 at ).
If the action [is] disowned by those in higher authority and appropriate action taken, it would be unlikely that ‘considerations of public policy relating to the integrity of the administration of criminal justice’ would require exclusion of the evidence in question (Ridgeway v R (1995) 184 CLR 19 at 53, 64;  HCA 66; cited in Nicholas v R (1998) 193 CLR 175 at  per Gaudron J).
(ix) ‘the difficulty (if any) of obtaining the evidence without impropriety or contravention of an Australian law’: s138(3)(h)
(i) Unfairness to a defendant
(ii) Other factors
Significant other sections that are or may be relevant
Other sections include:
Last updated: 4 March 2020