A natural extension of the circumstances in which the public policy discretion is enlivened occurred in Ridgeway v The Queen [1995] HCA 66; (1995) 184 CLR 19. It was held to apply to circumstances in which law enforcement authorities engage in unlawful conduct, not just to obtain evidence, but to procure the commission of the offence for which the accused is later prosecuted. As Brennan CJ pointed out in Nicholas v The Queen [1998] HCA 9; [1998] 193 CLR 173 at 197, the court has a duty to ensure that it does not exercise its discretionary powers to achieve an objective which "flagrant and deliberate breaches of the law" are designed to achieve. The majority in Ridgeway (p 32) cited with approval the statement by Deane J in Pollard v The Queen [1992] HCA 69; (1992) 176 CLR 177 at 203 which emphasised the need for the courts to ensure that they are not "demeaned by the uncontrolled use of the fruits of illegality in the judicial process". Their Honours concluded (p 35):

"At this stage, it suffices to say that, for the reasons given above, it should be accepted that a trial judge possesses a discretion to exclude, on public policy grounds, evidence of an offence or of an element of an offence in circumstances where its commission has been brought about by unlawful conduct on the part of law enforcement officers."

The majority in Ridgeway also held that the public policy discretion extends to circumstances where a criminal offence has been induced by improper, though not unlawful, conduct on the part of the authorities.

In expressing the same view, Gaudron J was also concerned with consequences of illegal conduct by law enforcement authorities. Her Honour said (p 77):

"But what is more important is that the administration of justice is inevitably brought into question, and public confidence in the courts is necessarily diminished, where the illegal actions of law enforcement agents culminate in the prosecution of an offence which results from their own criminal acts. Public confidence could not be maintained if, in those circumstances, the courts were to allow themselves to be used to effectuate the illegal strategems of law enforcement agents or persons acting on their behalf."

Although the public policy discretion was originally developed to apply to non-confessional evidence, subsequent decisions of the High Court have extended its application to confessional evidence (see Foster v The Queen (1993) 67 ALJR 550 at 554 and The Queen v Swaffield (1998) 192 CLR 159 at 178, 190 and 211).

It is against the background of those and other authorities of similar effect that Doyle CJ spoke in Question of Law Reserved (No. 1 of [1998] SASC 6634; 1998) 70 SASR 281 of the rationale underlying and the limits of the public policy discretion. In a judgment with which Cox and Matheson JJ agreed, the Chief Justice said (pp 287-288):

"The nature and scope of the [public policy] discretion has been considered in some detail by the High Court in recent times. I refer to Ridgeway v The Queen [1995] HCA 66; (1995) 184 CLR 19, R v Swaffield (1998) 72 ALJR 339 and Nicholas v The Queen [1998] HCA 9; (1998) 72 ALJR 456. There is no doubt that, in the exercise of that discretion, a court can exclude evidence other than confessional evidence. It is equally clear, in my opinion, that the discretion permits the exclusion of evidence only if that evidence was obtained by unlawful or improper conduct. The rationale underlying the exercise of the discretion to exclude evidence, if the discretion is so exercised, is that considerations of public policy may require the court to prevent the prosecution from gaining "curial advantage" by using improperly or unlawfully obtained evidence, and may require the court not to appear to approve of the illegality or impropriety by which the evidence was obtained, by allowing the use of the evidence as part of the prosecution case. When the court exercises the discretion, it declines to allow the prosecution to make use of evidence obtained through illegality or impropriety, because to do so would be to allow it to benefit by its own wrongdoing, and would give the appearance of approving of the relevant illegality or impropriety. Of course, as the cases make quite clear, the court has to put into the scales as well the importance of securing the conviction of those who commit criminal offences. Authority for what I have said is to be found in the manner in which the discretion is described, and the explanation given for its existence and exercise. I refer in particular to Bunning v Cross (at 74-75, 77-78) per Stephen and Aickin JJ; Ridgeway v The Queen (at 30-32) per Mason CJ, Deane and Dawson JJ, (at 48-49) Brennan J, (at 56) Toohey J, (at 74) per Gaudron J and (at 82-83) per McHugh J; Nicholas v The Queen (at 32-35) per Brennan CJ. If the evidence in question was not obtained by unlawful or improper means, this discretion does not arise. It does not arise simply because the discretion is directed to preventing the curial advantage that would be gained from the use of the evidence, and from avoiding the appearance of approval by allowing the use of the evidence. The discretion is a broad one. It is founded upon the need to preserve the integrity of the administration of justice and the need to protect the processes of the courts of justice: see Ridgeway (at 30-32) per Mason CJ, Deane and Dawson JJ. An object of the exercise of the discretion is to discourage illegal or improper conduct by the law enforcement authorities: see Ridgeway (at 32); R v Swaffield (at 22) per Brennan CJ. But the foundation of the discretion, and its object, do not give the courts a roving commission to search for illegality or impropriety by those responsible for the enforcement of the law. The discretion does not give a power to exclude evidence whenever there is some association between that evidence and illegal or improper conduct, or whenever an attempt is made to bolster prosecution evidence by resort to illegal or improper conduct. To exercise the discretion in that fashion would be to use the exclusion of evidence as a means of punishing wrongdoing by those responsible for the enforcement of the law. That is not the responsibility of the courts. Or, to be more precise, the exclusion of evidence is not the means by which wrongdoing is to be punished by the courts. As the majority said in Ridgeway (at 37) with reference to improper conduct by law enforcement officers in the course of investigating criminal activity:

"A finding that law enforcement officers have engaged in such clearly improper conduct will not, of course, suffice of itself to give rise to the discretion to exclude evidence of the alleged offences or of an element of it. As with the case of illegal conduct, the discretion will only arise if the conduct has procured the commission of an offence with which the accused is charged."

In other words, the discretion arises when the improper or illegal conduct has procured the commission of an offence or has enabled the prosecution to obtain the relevant evidence. As I have already said, it is when the illegality or impropriety is the means by which the evidence is procured that the discretion arises for consideration. It arises then because allowing the use of the evidence, obtained in this fashion, may appear to condone illegal or improper conduct, and may compromise the court's commitment to the upholding of the law." (my emphasis)

While acknowledging that Question of Law Reserved confined the ambit of the circumstances in which the public policy discretion is enlivened, the appellant argued that this Court in French v Scarman (1979) 20 SASR 333 did not limit the application of the public policy discretion to circumstances where the evidence was obtained by unlawful or improper conduct. French v Scarman was not brought to the Court's attention in Question of Law Reserved. The Solicitor-General accepted that French v Scarman may be inconsistent with the approach taken in Question of Law Reserved. He submitted that it is now appropriate to revisit the reasoning in French v Scarman which he suggested erroneously assumed that the public policy discretion was based upon considerations of unfairness.

In French v Scarman, the defendant had been subjected to a breath analysis test pursuant to the provisions of the Road Traffic Act 1961. The defendant requested that a sample of his blood be taken by a medical practitioner. The relevant provisions required the police to facilitate the taking of the sample of blood, but they failed to do so. The question under consideration was whether, in those circumstances, the Court had a discretion to exclude the lawfully obtained result of the breath analysis test.

The Full Court answered that question in the affirmative. It held that the failure of the police to comply with the requirement to facilitate the taking of a blood sample enlivened a discretion to exclude the evidence. Having referred to the judgment of Barwick CJ in Ireland in which the Chief Justice spoke of the principles relevant to the exclusion of evidence ascertained or procured by means of unlawful or unfair acts, King CJ, with whom Jacobs J and Williams AJ agreed, said (p 338):

"In one sense, of course, it can be said that the evidence constituted by the breath analysis was not unlawfully or unfairly obtained, because the obligation to submit to the breath test was not dependent upon compliance by the police with sub-s(2). In my opinion, however, sub-section (2) is a safeguard for the citizen expressly provided by the legislature and it is so closely connected with the obligation to submit to the breath test that non-observance by the police of the safeguard is a sufficient foundation for the discretion" (my emphasis).

King CJ referred to the need to weigh a number of competing considerations in considering the exercise of the discretion to exclude evidence "which is unlawfully, improperly or unfairly obtained" (p 339). He expressed the view that the conduct of the police went beyond a mere mistake and was, in a sense, deliberate. His Honour found that the police had deliberately refrained from asking the respondent directly whether he was requesting a blood test. He found that they were prepared to make use of what they thought was a technical defect in the form of the respondent's request in order to avoid implementing a statutory safeguard, namely, complying with their duty to do all things necessary to facilitate the taking of a blood sample. His Honour concluded that such an attitude to the safeguard merited condemnation. He concluded that "there was a conscious reluctance to implement the safeguard which resulted in actual, if perhaps unintended, illegality"(p 340).

In my opinion, King CJ applied the principles applicable to the public policy discretion rather than those applicable to the exercise of a general discretion based upon considerations of unfairness to the accused. A similar view of the approach adopted in French v Scarman was taken by Doyle CJ in Police v Jervis (1998) 70 SASR 429 at 439. King CJ was of the view that the principles in Bunning v Cross were attracted because, although the evidence of the breath analysis reading had been obtained lawfully and properly, the obtaining of that evidence was very closely connected in time and circumstances to the implementation of a statutory safeguard related to that evidence which the police unlawfully ignored.

The decision in French v Scarman was delivered in March, 1979, nine months after the decision in Bunning v Cross. As Doyle CJ observed in Jervis, since French v Scarman a number of decisions have not always distinguished between the public policy discretion identified in Bunning v Cross and a discretion based upon fairness to an accused. His Honour commented that the distinction has not always been drawn as clearly as it has been in recent years and that there is an added difficulty because of the area of overlap between the two types of discretion. The Court in Jervis was not asked to address whether French v Scarman is inconsistent with Question of Law Reserved.

In my opinion, the views expressed by Doyle CJ in Question of Law Reserved to which I have referred correctly state the law with respect to the application of public policy discretion and the rationale for the existence of that discretion. It might be said that the application of the public policy discretion to the circumstances in French v Scarman does not extend the area of operation of the discretion very far beyond the limits identified by Doyle CJ. Although the unlawful or improper conduct of the law enforcement authorities in French v Scarman was not directed to the obtaining of the evidence, it occurred immediately after the evidence had been obtained and was committed in connection with a safeguard provided by the legislation directed to the reliability of that evidence. I acknowledge the force of the argument that, in those circumstances, the application of the public policy discretion was justified in order to avoid the appearance of the court giving its imprimatur to the improper conduct of the law enforcement authorities which occurred so soon after the evidence was lawfully obtained. As a more extreme example, if law enforcement officers deliberately sabotage a safeguard with a view to placing an accused at a disadvantage in defending a charge, it can reasonably be argued that although the evidence was lawfully obtained, the prosecution is indirectly obtaining a curial advantage through that unlawful or improper conduct. To allow such advantage to persist through a trial might be perceived as permitting a misuse of the Court which could bring the administration of justice into disrepute.

In my opinion, however, the history of the public policy discretion has been centred upon the discretion being enlivened only when the evidence is obtained by unlawful, improper or unfair conduct on the part of law enforcement authorities. In identifying the rationale for the existence of the discretion, the High Court and other authorities have emphasised the importance of preventing the courts from being "demeaned" by the use of the "fruits of illegality" or being used "to effectuate the illegal stratagems of law enforcement agents or persons acting on their behalf." The focus is thus upon bringing the administration of criminal justice into disrepute through the use of the courts in this manner. The courts have not undertaken the role of supervising the conduct of law enforcement authorities generally in circumstances divorced from any attempt by those authorities to use the courts to further the aims of their unlawful, improper or unfair conduct.

The unlawful conduct of the law enforcement authorities in the matter under consideration and in French v Scarman did not offend the rationale identified by Doyle CJ in Question of Law Reserved. The critical element missing in both is an attempt by the prosecution to advance its case by using evidence obtained by or involving unlawful or improper conduct by a law enforcement authority. In my view, the history of the development of the public policy discretion and the rationale now identified for its existence do not sit well with the extension of its area of operation to encompass the possible exclusion of evidence obtained lawfully and without the occurrence of any unlawful, improper or unfair conduct on the part of the law enforcement officers in connection with the obtaining of the evidence. The authorities support the view expressed by Doyle CJ in Question of Law Reserved. If the public policy discretion is confined in the manner described by Doyle CJ in the passage earlier cited, for the reasons later discussed the interests of the accused are protected because circumstances such as those found in French v Scarman can fairly be encompassed within the ambit of a general unfairness discretion which has as its primary focus considerations of unfairness to the accused.

The learned trial judge said that if, contrary to his view, the public policy discretion was applicable, he would have declined to exclude the evidence in the exercise of that discretion. In view of the findings made by his Honour, in my opinion it would have been a proper exercise of his Honour's discretion to decline to exclude the evidence. If I was asked to exclude the evidence in the exercise of public policy discretion while sitting as the Court of Criminal Appeal, for the reasons later discussed I would decline to exclude the evidence. In my opinion, therefore, even if the public policy discretion was applicable, to the extent that the appeal is based upon his Honour's decision not to exclude the evidence in the exercise of the public policy discretion, the appeal fails.

As mentioned, the appellant also sought to rely upon a general discretion to exclude evidence, namely, a discretion focussed upon considerations of unfairness to the accused. In considering the exercise of such a general discretion, the question to be asked is whether receiving the evidence would be unfair to an accused in the sense that the trial would be unfair. In this context counsel relied on the decision of the High Court in Swaffield.

In discussing a general discretion focussed upon unfairness to an accused, it is necessary to avoid confusion between the types of discretion that involve the use of the word "unfair". First, the public policy discretion already considered can be enlivened if evidence is obtained by means of unfair conduct on the part of the law enforcement authorities. Barwick CJ in Ireland was concerned with evidence "procured by means of unlawful or unfair acts ..." (p 334). In Bunning v Cross, Stephen and Aicken JJ spoke of evidence which is "the product of unfair or unlawful conduct on the part of authorities" (p 75). As mentioned, the majority in Ridgeway extended the ambit of the public policy discretion to circumstances where a criminal offence has been induced by improper, though not unlawful, conduct on the part of the authorities. Unfair conduct could be encompassed within the expression "improper conduct". As discussed in the numerous authorities, however, in determining whether to exercise this discretion, the focus of the courts is not upon unfairness to an accused. Such unfairness is one of numerous factors to be taken into consideration and the weight to be given to it will vary.

Secondly, until the decision in Swaffield, in the special body of law governing the admissibility and discretionary rejection of confessional evidence, unfairness to an accused was relevant to the exercise of two independent but overlapping discretions. One of those independent discretions was the public policy discretion which I have already discussed. The other independent and overlapping discretion applied to confessional evidence had as its focus the question of unfairness to an accused. As discussed later in these reasons, in the context of confessional evidence the majority of the High Court in Swaffield replaced the overlapping public policy and unfairness discretions with a broader approach that I have later referred to as the "overall discretion". However, in an attempt to avoid confusion between discretions that have as their focus unfairness to an accused, in the discussion that follows I consider first the unfairness discretion as it has been applied to confessional evidence. The unfairness discretion applied to confessional evidence has been the subject of discussion in a number of High Court authorities. Following consideration of that particular unfairness discretion, I address the question of the existence of a more general unfairness discretion which is not limited in its application to confessional evidence.

The unfairness discretion developed in the context of confessional evidence was the subject of discussion by the High Court in Foster v The Queen [1993] HCA 79; (1993) 67 ALJR 547. In a majority judgment, four justices of the Court addressed the role of unfairness to an accused in the context of a voluntary confessional statement procured by unlawful police conduct. Their Honours said (p 554):

"It is now settled that in a case where a voluntary confessional statement has been procured by unlawful police conduct, a trial judge should, if appropriate objection is taken on behalf of the accused, consider whether evidence of the statement should be excluded in the exercise of either of two independent discretions. The first of those discretions exists as part of a cohesive body of principles and rules on the special subject of evidence of confessional statements. It is the discretion to exclude evidence on the ground that its reception would be unfair to the accused, a discretion which is not confined to unlawfully obtained evidence. The second of those discretions is a particular instance of a discretion which exists in relation to unlawfully obtained evidence generally, whether confessional or "real". It is the discretion to exclude evidence of such a confessional statement on public policy grounds. The considerations relevant to the exercise of each discretion have been identified in a number of past cases in the Court. To no small extent, they overlap. The focus of the two discretions is, however, different. In particular, when the question of unfairness to the accused is under consideration, the focus will tend to be on the effect of the unlawful conduct on the particular accused, whereas, when the question of the requirements of public policy is under consideration, the focus will be on "large matters of public policy" and the relevance and importance of fairness and unfairness to the particular accused will depend upon the circumstances of the particular case." (footnotes omitted) (my emphasis)

As is apparent from that passage, a discretion exists to exclude confessional evidence on the ground that its reception would be unfair to the accused. While their Honours specifically stated that this unfairness discretion is not confined to unlawfully obtained evidence, they also observed that the focus will tend to be on "the effect of the unlawful conduct" on the particular accused. The concept of unlawful conduct giving rise to the unfairness to the accused is also apparent in a number of other authorities concerned with discretionary exclusion of confessional evidence and may be a point of distinction from the more general unfairness discretion discussed later in these reasons.

Swaffield was a case involving confessional evidence. Brennan CJ discussed the "unfairness discretion" as a discretion which has as its purpose the safeguarding of an accused from the unfairness of using a confession in evidence against the accused at trial (pp 171-175). His Honour then discussed the public policy discretion and cited the passage from Foster to which I have previously referred. Having cited that passage, his Honour considered the overlap of the fairness and public policy discretions and said (p 181):

"The elements, or factors relevant to the exercise, of the two discretions to exclude a voluntary confession are substantially the same. Before either discretion is enlivened there has to be some illegality or impropriety on the part of law enforcement officers that results in the making of the confession." (my emphasis)

In the joint judgment of Toohey, Gaudron and Gummow JJ, their Honours referred to the power to exclude confessional evidence on the basis that it would be unfair to an accused to admit the statement. They summarised the purpose of that discretion as protecting the rights and privileges of an accused person (p 189). Identifying that unfairness is concerned with the right of an accused to a fair trial, their Honours cited the following passage from Van der Meer v The Queen [1988] HCA 56; (1988) 62 ALJR 656 at 666:

"[T]he question is not whether the police have acted unfairly; the question is whether it would be unfair to the accused to use his statement against him ... Unfairness, in this sense, is concerned with the accused's right to a fair trial, a right which may be jeopardised if a statement is obtained in circumstances which affect the reliability of the statement."

On the issue of reliability, in Swaffield their Honours also said (p 197):

"Unreliability is an important aspect of the unfairness discretion but it is not exclusive. As mentioned earlier, the purpose of that discretion is the protection of the rights and privileges of the accused. Those rights include procedural rights. There may be occasions when, because of some impropriety, a confessional statement is made which, if admitted, would result in the accused being disadvantaged in the conduct of his defence."

In the context of confessional evidence, most of the authorities have been concerned with the obtaining of confessional statements in circumstances involving some impropriety, unfairness or illegality on the part of law enforcement authorities that results in the making of the confessional statements. Although the focus is on whether it would be unfair to an accused to allow the statement to be used, the unfairness is usually linked to improper, unfair or illegal conduct on the part of law enforcement authorities. Unfairness may exist, for example, because the conduct produced a confession which is unreliable or because no confession might have been made if the investigation had been properly conducted (see Brennan J in Duke v The Queen [1989] HCA 1; (1989) 180 CLR 508 at 513). It was in the context of the authorities linking the unfairness to an accused with the improper, unfair or illegal conduct of the law enforcement authorities that Doyle CJ spoke in Jervis of the unfairness discretion discussed in Swaffield being enlivened if the unfairness to an accused is the product of illegality, impropriety or failure by law enforcement authorities to observe statutory requirements (pp 445-449). Doyle CJ also recognised, however, that unfairness to an accused in connection with confessional evidence can arise through no fault of the law enforcement authorities. His Honour used as an example the case of an admission made by an accused while suffering from severe shock, even if the person to whom it was made was unaware that the person was suffering from shock. His Honour observed that such circumstances could render the use of the confession unfair and that the law enforcement authorities might have, unwittingly, taken advantage of the state of the accused (p 448).

In principle, bearing in mind that the unfairness discretion to exclude confessional evidence is concerned with the right of an accused to a fair trial and not with the question as to whether the police have acted unfairly, in my opinion there is no reason why the unfairness discretion to exclude confessional evidence should be enlivened only if some illegality or impropriety on the part of law enforcement authorities resulted in the making of the confession. This was the view taken by Doyle CJ in R v Pfitzner [1996] SASC 5462; (1996) 66 SASR 161. His Honour expressed the view that, "in the absence of some direction from higher authority, the Court should proceed upon the basis that the discretion to exclude confessional statements on the grounds of unfairness is not confined to situations involving police impropriety"(p 180). The same view was taken by Fitzgerald J in Seymour v Attorney-General (Cth) and Ors [1947] ArgusLawRp 87; (1984) 53 ALR 513 at 527. However, as this appeal is concerned with the discretionary rejection of non-confessional evidence, it is unnecessary to take this issue any further.

It should also be borne in mind that, as mentioned, in the context of confessional evidence the overlapping public policy and unfairness discretions have been overtaken by a broader approach identified by the majority in Swaffield in the following terms (pp 194-195):

"[It is a better approach to think] of admissibility as turning first on the question of voluntariness, next on exclusion based on considerations of reliability and finally on an overall discretion which might take account of all the circumstances of the case to determine whether the admission of the evidence or the obtaining of a conviction on the basis of the evidence is brought at a price which is unacceptable, having regard to contemporary community standards."

"That the decided cases also reveal that one aspect of the unfairness discretion is to protect against forensic disadvantages which might be occasioned by the admission of confessional statements improperly obtained."

Kirby J also supported a re-expression of the tests of admissibility and discretionary exclusion of disputed confessions. His Honour said (p 207 and 208):-

"This would involve consideration, in turn, of three matters, namely whether the confession was voluntary; if so, whether it was reliable; and, if so, whether it should nonetheless be excluded from evidence in the exercise of an overall judicial discretion. This last consideration would permit attention to be given to factors which, in the past, this Court has accepted as relevant. They would include unfairness to the accused; disproportionate prejudice outweighing the probative value of such evidence; and relevant public policy considerations. The last might involve official conduct which was illegal or improper or which would otherwise involve securing the conviction of the accused at too high a price."

The content and ambit of operation of the "overall discretion" discussed in Swaffield remains to be defined. Counsel appeared to assume that the overall discretion is applicable to non-confessional evidence and, for reasons later discussed, this Court in Jervis proceeded on that assumption (p 449). However, I have reservations about attempting to apply that overall discretion to non-confessional material. This new discretion was enunciated in the context of confessional evidence and against a background of recognition by the criminal courts that a special body of law has been built around the admissibility and discretionary exclusion of confessional evidence. The passages to which I have referred specifically relate the overall discretion to confessions. There is nothing in the judgments of Swaffield to suggest that the overall approach should be given a wider application.

In my opinion, until the High Court determines otherwise, the preferred approach is to treat the overall discretion enunciated in Swaffield as limited to confessional evidence. However, if I am wrong in this view, for the reasons later discussed, in my opinion if the learned trial judge had considered the application of the overall discretion he would not have excluded the evidence and such a decision would have been well within the scope of his discretion. Similarly, for the reasons later discussed, if I was asked to exercise the discretion sitting as the Court of Criminal Appeal I would decline to reject the evidence.

There is a further aspect of the overall discretion upon which I should comment. In Jervis, the court appears to have assumed that the overall discretion is enlivened only if there exists some impropriety by a member of a law enforcement authority or if it would be unfair to use the evidence having regard to some such impropriety or if a law enforcement authority has taken advantage of some disadvantage under which the accused laboured. While that might appear to be a natural consequence of the combination of the public policy and unfairness discretions discussed in Swaffield, I doubt that the High Court intended to impose such a restriction. There is nothing in the language of the majority to suggest that it favoured such an approach. The principle underlying the existence of the new discretion and the passage from the judgment of Kirby J to which I have referred do not sit well with that restriction. For present purposes, however, it is unnecessary to take that discussion any further.

The written and oral submissions of both counsel concentrated upon the application to the circumstances before the Court of the unfairness discretion as described in Swaffield. I have reservations about such an approach. As Doyle CJ observed in Jervis, the tenor of the High Court pronouncements is against its application to non-confessional evidence. For example, in the passage earlier cited from Foster, the Court specifically identified the public policy discretion as applying to "unlawfully obtained evidence generally, whether confessional or real", but did not refer to the unfairness discretion as applying beyond confessional evidence. In some circumstances, the principles concerned with discretionary rejection of confessional evidence may not be readily translated into operation in connection with the discretionary rejection of non-confessional material. If the unfairness discretion developed in the context of confessional material is not enlivened unless there is some illegality or impropriety on the part of law enforcement officers that results in the making of the confession, that particular unfairness discretion would not be applicable to the circumstances now under consideration.

For the reasons that follow, in my opinion there is a further head of discretion to exclude admissible evidence which is based upon unfairness to an accused and which overlaps in many respects with the unfairness discretion concerned with confessional evidence. It is a separate power or discretion to exclude admissible evidence. The differences between these unfairness discretions may be marginal, but as the law presently stands, in my opinion, it is appropriate to recognise the discretion I am about to discuss as separate from and additional to the unfairness discretion that was applicable to confessional evidence.

The concept of unfairness to an accused has been used to describe the basis of a general discretion to exclude evidence which, in principle, applies to any evidence. The existence of such a general discretion was recognised in Driscoll v The Queen [1977] HCA 43; (1977) 137 CLR 517. In the context of an issue as to the admissibility of an unsigned document recording an interview between an accused and the police, Gibbs J with whom Mason, Jacobs and Murphy JJ agreed, said (p 541):

"Although as a matter of law a document is admissible against an accused person who has adopted it, that does not seem to me to be the end of the matter. It has long been established that the judge presiding at a criminal trial has a discretion to exclude evidence if the strict rules of admissibility would operate unfairly against the accused. The exercise of this discretion is particularly called for if the evidence has little or no weight, but may be gravely prejudicial to the accused: see, e.g., R v Christie [1914] AC 545 at p 560; Noor Mohamed v The King [1949] AC 182 at p 192; Harris v Director of Public Prosecutions [1952] AC 694 at p 707 and Kuruma v The Queen [1955] AC 197 at p 204". (my emphasis)

Nearly a year later in their joint judgment in Bunning v Cross, Stephen and Aicken JJ also recognised the existence of such a discretion. Their Honours drew a distinction between the public policy discretion they were considering and a "general discretion" discussed by Lord Widgery CJ in Jeffrey v Black [1978] QB 490 which their Honours said applied in "all criminal cases". Stephen and Aicken JJ said of the decision in Jeffrey v Black (p 74):

"More recently still, in Jeffrey v Black Lord Widgery CJ, in a case involving evidence procured by an unlawful search, applied Kuruma's Case on the admissibility of the evidence and went on to describe the relevant discretion as no more than that general discretion "which every judge has all the time in respect of all the evidence which is tendered by the prosecution". It was a discretion to be exercised when it would be "unfair or oppressive" to allow particular evidence to be called by the prosecution but was applicable only to "very exceptional situations".

Gibbs CJ spoke again of a general unfairness discretion in the context of identification evidence in Alexander v The Queen [1981] HCA 17; (1981) 145 CLR 395 at 402. His Honour said:

"The authorities support the conclusion that I have reached, which is that, as a matter of law, evidence of an identification made out of court by the use of photographs produced by the police is admissible. However, a trial judge has a discretion to exclude any evidence if the strict rules of admissibility operate unfairly against the accused. It would be right to exercise that discretion in any case in which the judge was of opinion that the evidence had little weight but was likely to be gravely prejudicial to the accused." (my emphasis)

Murphy J expressed a similar view and referred to Ireland and Driscoll (p 435).

In Stephens v The Queen [1985] HCA 30; (1985) 156 CLR 664, the High Court was again concerned with the admissibility of an unsigned written record of a conversation between the accused and investigating police. In a joint judgment, the Court held that where there is evidence that an accused has read a record of an interview and acknowledged it to be correct, as a matter of strict law the written record is admissible. The Court went on to say (p 669):

"However the judge presiding at a criminal trial always has a discretion to exclude evidence if the strict rules of admissibility would operate unfairly against the accused ..."

The existence of the discretion under consideration is also consistent with the residual discretion to exclude admissible evidence identified as existing where objection is taken to evidence which discloses an accused's bad character. This type of evidence is commonly referred to as similar fact or propensity evidence. For example, in Harriman [1989] HCA 50; (1989) 167 CLR 590, Brennan J said (pages 594 and 595):

"As the argument against admissibility in this case relied on the judicial discretion to reject evidence otherwise admissible when it is necessary to do so to secure a fair trial, it is necessary to say something about the scope of the discretion. Is there a residual judicial discretion to reject evidence revealing the commission of another offence or a predisposition to commit an offence on the ground that its prejudicial effect is disproportionate to its probative effect when the evidence is found to be admissible because its probative force clearly transcends its merely prejudicial effect? Obviously, the occasions for the exercise of such a discretion are hard to envisage, for evidence which satisfies the criterion of admissibility is unlikely to attract the exercise of the discretion. Nevertheless, one cannot exclude the possibility of a case where, despite the substantial probative force of the evidence, fairness dictates its exclusion. As against the prospect of such an exceptional case arising, the continued existence of the residual discretion should be admitted."

In 1992, the High Court confirmed that an accused has a right to a fair trial in Dietrich v The Queen [1992] HCA 57; (1992) 177 CLR 292. In the course of her judgment, Gaudron J spoke of the requirement that a trial be fair and how that requirement may impinge upon evidentiary and procedural rules. Her Honour then said (pp 363-364):

"...Speaking generally, the notion of "fairness" is one that accepts that, sometimes, the rules governing practice, procedure and evidence must be tempered by reason and commonsense to accommodate the special case that has arisen because, otherwise, prejudice or unfairness might result. Thus, in some cases, the requirement results in the exclusion of admissible evidence because its reception would be unfair to the accused in that it might place him at risk of being improperly convicted, either because its weight and credibility cannot be effectively tested or because it has more prejudicial than probative value and so may be misused by the jury. In other cases, the procedures may be modified, for example, to allow evidence to be given through an interpreter, or to allow for special directions to counteract the effect of pre-trial publicity or even something said or done in the trial itself. Sometimes the venue may be changed to counteract some perceived difficulty in obtaining a fair trial in the area in which the offence was committed; in other cases proceedings may be adjourned, for example, to enable evidence to be checked or to allow for pre-trial publicity to abate. The examples are not exhaustive. They are, however, sufficient to show that the requirement of fairness is, and, in various different contexts, has been recognized as, independent from and additional to the requirement that a trial be conducted in accordance with the law. The requirement of fairness is not only independent, it is intrinsic and inherent. According to our legal theory and subject to statutory provisions or other considerations bearing on the powers of an inferior court or a court of limited jurisdiction, the power to prevent injustice in legal proceedings is necessary and, for that reason, there inheres in the courts such powers as are necessary to ensure that justice is done in every case. Thus, every judge in every criminal trial has all powers necessary or expedient to prevent unfairness in the trial. Of course, particular powers serving the same end may be conferred by statute or confirmed by rules of court. The notion of a fair trial and the inherent powers which exist to serve that end do not permit of "idiosyncratic notions of what is fair and just" any more than do other general concepts which carry broad powers or remedies in their train. But what is fair very often depends on the circumstances of the particular case. Moreover, notions of fairness are inevitably bound up with prevailing social values. It is because of these matters that the inherent powers of a court to prevent injustice are not confined within closed categories. And it is because of those same matters that, save where clear categories have emerged, the inquiry as to what is fair must be particular and individual. And, just as what might be fair in one case might be unfair in another, so too what is considered fair at one time may, quite properly, be adjudged unfair at another." (footnotes omitted) (my emphasis)

The distinction drawn by Stephen and Aicken JJ in Bunning v Cross between the discretion to exclude evidence on the basis of unlawfulness and the discretion to exclude on the basis of unfairness to the accused was cited by Brennan J in Ridgeway (p 48). His Honour then observed (p 49):

"The purpose of the discretion to exclude evidence on the ground of unfairness is to ensure a fair trial for the accused; the purpose of the discretion to exclude evidence on the ground of unlawfulness is not to ensure a fair trial but to ensure that the conviction of the alleged offender is not bought at too high a price by reason of curial approval of - if not reward for - illegal conduct on the part of the law enforcement agency." (my emphasis)

Citing Gibbs CJ in Alexander, the New South Wales Court of Criminal Appeal acknowledged the existence of a general discretion based on unfairness to an accused in R v Tillott (1995) 38 NSWLR 1 at p 7. The court in Tillott was concerned with the admissibility of the evidence of a witness who had undergone Eye Movement Desensitisation Reprocessing. In a different context concerning the discretion to exclude evidence of an unlawfully intercepted telecommunication, the New South Wales Court again confirmed the existence of such a general discretion in R v Edelsten (1990) 21 NSWLR 542 at pp 553-554.

In R v McLean and Funk, ex parte Attorney-General [1991] 1 Qd R 231, the Queensland Court of Criminal Appeal was asked to consider whether a court had the power to exclude the evidence of a competent witness who was an indemnified accomplice. In the course of his judgment, Kelly SPJ said (p 236):

"In dealing with the first question, the starting point must necessarily be the fundamental principle that the judge presiding at a criminal trial always has a discretion to exclude evidence if the strict rules of admissibility would operate unfairly against the accused (Driscoll v. The Queen [1977] HCA 43; (1977) 137 C.L.R. 517, 541; Stephens v. The Queen [1985] HCA 30; (1985) 156 C.L.R. 664, 669; Bunning v. Cross [1978] HCA 22; (1978) 141 C.L.R. 54, 73-74). The principle is stated in slightly different terms in R. v. Sang [1979] UKHL 3; [1980] A.C. 402 although the effect is the same. Lord Salmon, at 444-445, expressed it thus: "I consider that it is a clear principle of the law that a trial judge has the power and the duty to ensure that the accused has a fair trial. Accordingly, amongst other things, he has a discretion to exclude legally admissible evidence if justice so requires: see Lord Reid's speech in Myers v. Director of Public Prosecutions [1965] A.C. 1001, 1024." Lord Salmon had, at 444, expressed the view that the decision as to whether evidence may be excluded depends entirely upon the particular facts of each case and the circumstances surrounding it, which are infinitely variable and, at 445, he also gave it as his opinion that the category of cases in which technically admissible evidence may be rejected on the ground that it would make the trial unfair is not and can never be closed except by statute. Lord Fraser of Tullybelton, at 447, after referring to some categories of cases where legally admissible evidence has been excluded in the exercise of a discretion, went on to say: "These cases are in my opinion examples of the exercise of a single discretion founded upon the duty of the judge to ensure that every accused person has a fair trial." Specifically Lord Fraser went on to express the opinion, also at 447, that the discretion is not limited to excluding evidence which is likely to have prejudicial effects out of proportion to its evidential value. In Australia this particular exclusion is expressed in a more limited way as "where the evidence has little or no weight but may be gravely prejudicial to the accused" (Driscoll at 541) and as "where a comparison of the smallness of the probative value of the evidence with its considerable prejudice to the fair trial of the matter justifies its exclusion" (Bunning v. Cross at 64-65) and also as "where the evidence in question is of relatively slight probative value but is highly prejudicial to the accused" (idem at 74). In the lastmentioned passage Stephen and Aickin JJ. referred to this as perhaps the most common instance of the general discretion to exclude admissible evidence when to admit it will be unfair to the accused. To return to R. v Sang, in dealing with the general discretion Lord Scarman, at 453, said: "Notwithstanding its development case by case, I have no doubt that the discretion is now a general one in the sense that it is to be exercised whenever a judge considers it necessary in order to ensure the accused a fair trial.""

Later in his judgment, Kelly SPJ expressed the following conclusion (p 239):

"After consideration of what has been said in all of the cases to which I have referred above on the subject of what has been referred to as the general discretion and on the application of that discretion in the case of an indemnified witness, I have reached the conclusion that because of the undoubted discretion which a judge presiding in a criminal trial has to exclude evidence if the strict rules of admissibility would operate unfairly against the accused, that is, in carrying out his duty to ensure that the accused has a fair trial, the discretion does exist to exclude the evidence of a competent witness, whether or not that witness be an accomplice, who can give evidence of the commission of the offence charged in the indictment and has received an indemnity from prosecution."

Derrington J was also of the view that the court possesses a general discretion to exclude evidence based upon considerations of unfairness to an accused. Although Carter J dissented as to the application of the discretion and the result of the appeal, his Honour cited Driscoll and Stephens and accepted that such a discretion exists.

The Victorian Court of Appeal has taken the same view. In Rozenes and Anor v Beljajev and Ors [1995] VicRp 34; [1995] 1 VR 533, the Court was asked by the Crown to quash a ruling of the trial judge that the evidence of an indemnified accomplice be excluded from the trial. Described by the Court of Appeal as "the backbone of the Crown case" (p 543), the evidence was excluded in its entirety. The critical question argued before the Court was the correctness of the ruling concerning the existence and scope of a discretion to exclude evidence of an accomplice on the ground of its reliability. It was argued in addition that, on the assumption that such a discretion existed, the learned trial judge erred in a number of ways in the exercise of that discretion.

In a joint judgment, the Court referred to a number of authorities concerned with the possible exclusion of the evidence of accomplices. They observed that there was no example of which they were aware where the evidence of an accomplice had been excluded solely on the ground of its unreliability. Faced with a Crown proposition that there is no general or residual discretion to exclude evidence on the ground that to receive it would be unfair to the accused, the Court referred to the views expressed in Edelsten and in McLean and Funk. The Court's conclusion is summarised in the following passage (p 549):

"In the present case the defendants accept that unfairness to the defendant means, not unfairness in some general sense, but that the defendant will not receive a fair trial. It is fundamental to our system of criminal justice that a person should not be convicted of an offence save after a fair trial according to law: Dietrich v R [1992] HCA 57; (1992) 177 CLR 292 at 299-300 per Mason CJ and McHugh J. , at 326 per Deane J and at 362 per Gaudron J. The proposition must be accepted that there is a discretion in a criminal case to reject any evidence, whether or not a confession, on the ground that to receive it would be unfair to the accused in the sense that the trial would be unfair. So much must be accepted both on principle and by reason of the authorities." (my emphasis)

In South Australia, the Court of Criminal Appeal in Jervis was concerned with the question of discretionary exclusion of non-confessional evidence. However, the appeal proceeded on the assumption that the unfairness discretion discussed in Swaffield was available. Doyle CJ specifically said he was not to be taken as deciding that the Swaffield unfairness discretion was applicable to non-confessional evidence and he observed that the general tenor of the High Court pronouncements left him with a doubt as to its availability outside the realm of confessional evidence. It appears that the Court was not taken to the High Court or Queensland authorities to which I have referred and was not asked to consider whether a more general unfairness discretion exists in addition to the Swaffield unfairness discretion. Although reference was made to Edelsten and Rozenes v Beljajev, it was a reference for the purposes of considering the ambit of the Swaffield unfairness discretion and whether, given the requirement to ensure that an accused receives a fair trial, the Swaffield unfairness discretion should be limited to non-confessional evidence. The Court in Jervis was not deciding whether a further head of discretion based on unfairness to an accused exists in addition to the Swaffield unfairness discretion.

Similarly, in Police v Fountaine [1999] SASC 227; (1999) 74 SASR 26 at 44, although reference was made to the use of the discretions discussed in Swaffield as a basis for excluding evidence of the analysis of blood in circumstances where there was failure to comply with the provisions of the Road Traffic Act 1961, the question as to the existence of a further head of discretion had not been the subject of submissions. The issue raised in Fountaine was centred upon the admissibility of such evidence and whether the previous decision of this Court in R v Turner (1975) 12 SASR 373 that such evidence was inadmissible should be overruled. In these circumstances, I do not regard Fountaine as an authority standing against the existence of a general unfairness discretion separate from the unfairness discretion discussed in Swaffield.

In Cross on Evidence, 6th Aust. ed., the learned author identifies a number of categories of what are commonly called "discretions" to exclude relevant and otherwise admissible evidence. Having identified four categories which include the rejection of evidence where its prejudicial effect exceeds its probative value, the discretion to reject a confession if it would be unfair to use it against an accused and the discretion to reject evidence, including a confession, on the ground that it has been unlawfully obtained, the learned author says: (para.11125)

"(e) There is a residual discretion to reject any evidence if the strict rules of admissibility would operate unfairly against the accused - that is, it is rejected on the ground that to receive it would be unfair to the accused in the sense that the trial would be unfair. It has been said that, confessions apart, it is not easy to think of circumstances in which grounds might exist for the exercise of that residual discretion in relation to any evidence which would not fall within the more specific principle that evidence will not be admitted where its prejudicial effect exceeds its probative value. The unreliability of a witness has been held not to attract the discretion, on the ground that this interferes unduly with the division of function between judge and jury, and would amount to an anticipatory ruling which would, by reason of Doney v R [(1990) [1990] HCA 51; 171 CLR 207], be erroneous if given at the close of the Crown case. A difficult area of potential application concerns accomplices. An example of the discretion may exist where the weight and credibility of the evidence cannot be effectively tested. Another example may exist in relation to excessively inflammatory evidence such as gruesome photographs." (footnotes omitted)

Bearing in mind the statements in the authorities to which I have referred, in my opinion a discretion exists to exclude non-confessional evidence on the ground that to receive it would be unfair to an accused in the sense that the trial would be unfair. The existence of the discretion is not dependent upon the conduct of law enforcement authorities. An accused person is entitled to a fair trial and it is the duty of the court to attempt to ensure that the trial is fair (see Barton v The Queen [1980] HCA 48; (1980) 147 CLR 75, Jago v District Court (NSW) [1989] HCA 46; (1989) 168 CLR 23 and Dietrich). The existence of this discretion is inherent in that duty of the court. For ease of reference I will refer to this discretion as the "general unfairness discretion".

As indicated earlier, in principle the general unfairness discretion applies to any evidence. However, this appeal is concerned with non-confessional evidence and it is unnecessary to consider whether the general unfairness discretion now applies to confessional evidence. It could reasonably be argued that the overall discretion enunciated in Swaffield and now applicable to confessional evidence "covers the field" and incorporates all aspects of the general unfairness discretion. If, however, contrary to my view, the overall discretion is enlivened only if there exists some impropriety as discussed earlier in these reasons (par58), there remains room for the application of the general unfairness discretion in the area of discretionary rejection of confessional evidence.

It is also unnecessary to examine in any detail the application of the general unfairness discretion to particular fact situations or to other areas in which special bodies of law already exist in connection with the admissibility and discretionary exclusion of particular types of evidence. The principles concerned with evidence of bad character are an example of such a special body of law. Where special bodies of law exist, the general unfairness discretion may overlap with well established principles. In those circumstances, the opportunity for the operation of the general unfairness discretion is likely to be limited and the weight to be given to the various relevant factors will be determined or influenced by the special principles governing the admissibility and discretionary exclusion of the special type of evidence under consideration. In other circumstances, although a special body of law may not exist, the courts may have considered the exercise of the general unfairness discretion in the context of particular fact situations and given guidance as to the application of the discretion to such fact situations. For example, a number of authorities, including McLean and Funk and Rozenes v Beljajev, have dealt with the possibility of discretionary exclusion of the evidence of accomplices and indemnified witnesses. In Rozenes v Beljajev the Court discussed the limits of the discretion and also sounded a warning as to the likely room for the operation of the general unfairness discretion (p 549):

"But while the existence of a residual discretion must be accepted, it is not easy to think of circumstances in which grounds might exist for the exercise of that residual discretion in relation to any evidence - we are not speaking of confessions - which would not bring the case within the more specific principle whereby evidence is not to be admitted where its prejudicial effect is out of proportion to its probative value. (It may be that the admissibility of a written statement and the unavailability of its maker for cross-examination could in an appropriate case be treated as an example of such circumstances: ...)."

In the context of a submission that unfairness existed by reason of the unreliability of the evidence having regard to the strong motive which the accomplice had for falsely implicating the accused in the offence charged, the Court in Rozenes v Beljajev discussed the meaning of "unreliability" for that purpose. It said that "unreliability" for that purpose does not mean the actual falsity or inaccuracy of the evidence, but means "the risk or probability that, by reason of the position of the accomplice, his evidence will be false or inaccurate". After referring to a number of authorities, the Court said (p 553):

"As we have said, we do not think that one can dispute the proposition that, quite apart from the other circumstances which have been authoritatively accepted as giving rise to the discretion to exclude admissible evidence in a criminal trial, the discretion arises whenever it is shown that the reception of certain evidence will be unfair to the accused. But, as we have said, once it is accepted that this proposition does not commit to the judge a broad and undefined discretion to determine what is in all the circumstances fair, but requires the judge to consider whether reception of the evidence will make the trial unfair, it becomes difficult to think of a set of circumstances which might give rise to the discretion in cases where it is not suggested that there is a disproportion between the probative value of the evidence and its prejudicial effect. In particular, as Carter J. observed at 255 in McLean and Funk, it is difficult to see how it can be said that the trial is unfair by reason of the unreliability of evidence which is probative where the circumstances which make the evidence unreliable are properly exposed for the consideration of the jury. His Honour went on to conclude at 260 that there was no discretion to exclude evidence which was based wholly or primarily upon the trial judge's conclusion that the evidence was unreliable: the exercise of such a discretion interfered with one of the most integral of the jury's functions, a function which there was no reason to believe any properly instructed jury to be incapable of properly performing. We are, with respect, in general agreement with the view of Carter J. on these questions. As Dixon J. once said: "...At bottom the choice is between the course of placing before the jury material which bears upon the case, leaving them to judge of its reliability and probative value, and the course of withholding it from them on the ground that there is too much danger in their taking into consideration matter which by reason of its source or provenance is prima facie dubious and untrustworthy." (Sinclair v R [1946] HCA 55; (1946) 73 CLR 316 at 333). The approach of the courts has been and should be one with a very strong predisposition to the view that, questions of fact and credibility being for the jury and the jury being an institution in whose capacity and integrity confidence is reposed by the courts, evidence which is probative should go to the jury despite its infirmities, accompanied by the trial judge's directions concerning the considerations, both general and particular, affecting its reliability, including of course in an appropriate case the matter of corroboration. Trial judges must be at pains to ensure that the discretion to exclude admissible evidence on the ground of unfairness is not used (contrary to Doney) to withdraw a case from the jury on the footing that any conviction would be unsafe or unsatisfactory. The judge in the present case has really exercised the discretion to reject admissible evidence on the ground of unfairness on the basis that a conviction based on the apprehended Crown case would be unsafe or unsatisfactory, and has, so to speak, given in favour of the defence an anticipatory ruling (in the light of the apprehended or hypothetical Crown case) which Doney would show to be erroneous had it been given at the close of the Crown case."

After a clear and helpful discussion in which the need for caution and limits on the exercise of a discretion to exclude evidence on the basis of unreliability was emphasised, the Court said (p 559):

"We accept the view of Carter J. that there is no discretion to exclude evidence which is based wholly or primarily upon the trial judge's conclusion that the evidence is unreliable. But if this view be too extreme, then at least it would have to be said that the circumstances calling for a favourable exercise of the discretion would have to be most exceptional. For it could only be in a most exceptional case that one could say, as Vincent J. put it in Peirce [1992] VicRp 17; [1992] 1 VR 273 at 277 that the considerations affecting reliability were not "comprehensible to a jury and capable of assessment by them as the proper tribunal of fact". The circumstances of the present case could not be regarded as most exceptional for this purpose."

The warning in Rozenes v Beljajev concerning the need to avoid usurping the function of the jury should be heeded. In addition, as Gaudron J observed in Dietrich in the passage to which I have referred, the inherent powers used to serve the purpose of achieving a fair trial "do not permit of idiosyncratic notions of what is fair and just." Nevertheless, for these purposes the concept of fairness to an accused is a broad one and the remarks of the majority in Swaffield, although made in the context of the unfairness discretion concerned with confessional evidence, are equally applicable to the operation of the general unfairness discretion. The purpose of both discretions includes the protection of "the rights and privileges of the accused", which rights "include procedural rights" (pp 189 and 197). Both discretions look "to the risk that an accused may be improperly convicted" (p 189). If the admission of the evidence would create a perceptible risk of a miscarriage of justice that cannot adequately be dealt with by appropriate directions to the jury, the proper exercise of the general unfairness discretion would require exclusion of the evidence. In those circumstances the admission of the evidence would result in an unfair trial. In determining whether such a perceptible risk cannot adequately be dealt with by appropriate directions, however, the capacity of juries to understand, appreciate and apply directions should not be underestimated. In circumstances where the admission of the evidence would cause unfairness, but not to the extent of creating a perceptible risk of miscarriage of justice or a perceptible risk that could not be adequately avoided by directions, the nature and extent of the unfairness will need to be assessed as will matters such as the probative and prejudicial value of the evidence and its importance to the prosecution case. The court may need to weigh factors such as those that are considered in the context of the public policy discretion. In this way, the type of circumstances that existed in French v Scarman are encompassed within the general unfairness discretion. The factors to be weighed may well include the conduct of the law enforcement authorities and whether that conduct has contributed to the unfairness. For example, if the conduct of the authorities occurred with a view to placing an accused at a forensic disadvantage, and a disadvantage ensued, such conduct and the existence of the disadvantage would be highly relevant in determining whether the evidence should be excluded. This approach is consistent with the view taken by the Court of Appeal in Callis v Gunn [1964] 1 QB 495. In a judgment with which the other members of the Court agreed, Lord Parker CJ said (p 501):

"[A]s is well known, in every criminal case a judge has a discretion to disallow evidence, even if in law relevant and therefore admissible, if admissibility would operate unfairly against a defendant. I would add that in considering whether admissibility would operate unfairly against a defendant one would certainly consider whether it had been obtained in an oppressive manner by force or against the wishes of an accused person. That is the general principle."

Having identified the nature of the general unfairness discretion, it is appropriate also to discuss briefly the relationship between this discretion and the discretion that has commonly been referred to as "the Christie discretion". It has generally been accepted that the Christie discretion is a separate head of discretion based upon a consideration of the probative weight of the evidence in comparison with its prejudicial effect. However, in the passage from Driscoll to which I have referred, Gibbs J identified the Christie discretion as an example of the application of the general unfairness discretion. Stephen and Aicken JJ appear to have taken the same view in Bunning v Cross (pp 74 and 75).

In Swaffield, Brennan CJ identified the Christie discretion as a "further possible category of exclusion of evidence including voluntary confessional statements" (p 183). Having referred to Christie, Brennan CJ spoke of a "more robust approach to exclusion taken in later cases" and cited the passage from Driscoll to which I have referred. The majority in Swaffield spoke of the Christie-type discretion as a basis of discretionary rejection of confessional evidence which "focuses on the probative value of the statement, there being a power, usually referred to as a discretion, to reject evidence the prejudicial impact of which is greater than its probative value." (p 189). The majority identified the purpose of the power or discretion as "to guard against a miscarriage of justice" (p 189), and later referred to authorities where this type of discretion was applied in connection with similar fact or propensity evidence. The majority said (p 192):

"However, as a matter of principle there is no reason why the power or discretion to exclude evidence which is unduly prejudicial should not extend to a statement made by an accused person and to other evidence upon which it would be dangerous for a jury to act".

After referring to a number of authorities, their Honours said (p 193):

"However, the fairness at issue in cases involving the exercise of a discretion to exclude unduly prejudicial evidence is the fairness of the trial, in the sense of a trial that does not involve a perceptible risk of a miscarriage of justice. Since "the unfairness discretion" is a recognised basis for excluding confessional statements and is dealt with in the authorities as a discreet discretion, the issue whether there is some additional basis for excluding such statements in terms of probative value versus prejudicial effect does not call for further exploration in the present context. Where confessional statements have been excluded in the exercise of the unfairness discretion, it has not been after a weighing of probative value against prejudicial effect has been carried out."

For the purposes of the present appeal, it is unnecessary to decide whether the Christie discretion is a separate head of discretion or is a particular example of the application of the general unfairness discretion. There may be little difference in practice. However, I favour the view that it is more appropriate to recognise the Christie discretion as an example of the application of the general unfairness discretion. In this way the exercise of the discretion is not fettered by the strictness that tends to accompany categories and all relevant factors, including the probative value in comparison with the prejudicial value, can be taken into account by the court. The majority in Swaffield identified the purpose of guarding against a miscarriage of justice as the purpose of the Christie-type discretion. The general unfairness discretion as I have described it achieves this purpose.

In the matter under consideration, the learned trial judge was not asked to consider the application of the general unfairness discretion as a basis of exclusion separate from the public policy discretion. To the extent that he failed to consider the application of the general unfairness discretion, his Honour was in error. However, it is clear from his Honour's remarks that he did not consider that any significant unfairness had been caused to the appellant by reason of the unlawful destruction of the cannabis. His Honour's view is summarised in the following paragraphs from his reasons:

"56. The real thrust of the accused's allegations as to prejudice are that he cannot check the initial analyst's certificate, and has lost the opportunity to put the prosecution to proof of its case against him. In my view he has relevantly lost little regarding a checking of the initial analysts certificate. Importantly, he has not denied that the material found in his car and in his house was cannabis and he seems to have agreed that it was. And, as indicated above, the most cogent and relevant evidence as to weight is the weight when seized." 57. The Crown Prosecutor indicated during the voir dire hearing that the initial analyst would be called by the prosecutor to give evidence (if the accused wished) and he would not rely upon any statutory proof of the facts stated in the certificate by merely producing it and tendering it (see s.61(2) of the Controlled Substances Act). 58. In all the circumstances, I am unable to find that the accused would suffer any prejudice if I were to allow the evidence of what is contained in the two certificates referred to in the application, and the cannabis which has not been destroyed and was the subject of later analysis."

In view of the error by the learned trial judge to which I have referred, this Court could refer the matter back to the learned trial judge for him to consider the exercise of his discretion in accordance with the decision of this Court. However, in my opinion it is clear that his Honour would not exclude the evidence in the exercise of the general unfairness discretion. If this Court was asked to exercise that discretion, in my opinion it should decline to do so. While the conduct of the police in destroying the cannabis was unlawful, it was not a deliberate breach of s 52A of the Act. There is no element of the court giving its imprimatur to the unlawful conduct. The evidence of the analysis is critical to the prosecution case. Although the appellant has lost the opportunity to test the prosecution evidence through analysis conducted by an analyst of the appellant's choice, in the particular circumstances of this case there is no reason to doubt the reliability of the evidence of identification led by the prosecution in the sense in which "reliability" was explained in Rozenes v Beljajev. Photographs of the material were taken. The appellant did not cross-examine the analyst and did not deny that the material was correctly identified as cannabis. The entire conduct of the defence case lacks any suggestion of an attack upon the merits of the evidence. Rather it seeks to rely upon a mistake by a police officer not connected with the investigation without demonstrating any sound basis for a conclusion that the error by that officer has created any genuine unfairness to the appellant or any risk of a miscarriage of justice.

By way of summary, the following is an outline of the conclusions I have reached concerning discretionary exclusion of evidence:-

(i) a court has a discretion to exclude confessional evidence in the exercise of the overall discretion enunciated in the majority judgment and by Kirby J in Swaffield; (ii) until the High Court determines otherwise, the overall discretion should be regarded as limited to confessional evidence; (iii) prior to Swaffield, discretionary exclusion of confessional evidence was based upon two independent but overlapping discretions, namely, the public policy discretion and a discretion which had as its focus unfairness to an accused; (iv) the public policy discretion also extends to non-confessional evidence; (v) the public policy discretion, whether in the context of confessional or non-confessional evidence, is enlivened only if the evidence was obtained by unlawful or improper conduct or if the criminal offence was induced by unlawful or improper conduct on the part of law enforcement authorities; (vi) the authorities are not consistent as to whether the unfairness discretion formerly applicable to confessional evidence was enlivened only if some unlawful or improper conduct on the part of law enforcement authorities resulted in the making of the confession; (vii) a discretion exists to exclude non-confessional evidence on the ground that to receive it would be unfair to an accused in the sense that the trial would be unfair: * the purpose of this discretion is to ensure that an accused person receives a fair trial and is not improperly convicted. * the operation of this discretion is not dependent upon the conduct of law enforcement authorities; * in principle, this discretion applies to any evidence, but in those areas where special bodies of law exist with respect to the admissibility and discretionary exclusion of particular types of evidence, this discretion may be subsumed by or overlap with well established principles; (viii) I agree with the observations of Doyle CJ concerning the application of and scope for the exercise of the general unfairness discretion. (ix) The Christie discretion based upon a comparison of probative and prejudicial values should be seen as an example of the application of the general unfairness discretion.

For the reasons discussed, in my opinion the learned trial judge was correct in determining that the public policy discretion was not applicable. If, contrary to my view, that discretion did apply to the circumstances under consideration, it is apparent that his Honour would not have exercised that discretion to exclude the evidence. Sitting as the Court of Criminal Appeal, I would not exclude the evidence. Similarly, if I am wrong and the overall discretion enunciated in Swaffield was applicable, in my view his Honour would not have exercised that discretion to exclude the evidence and, if asked, this Court should also decline to exclude the evidence.

As to the application of the general unfairness discretion, although his Honour erred in failing to consider the exercise of that discretion, for the reasons discussed in my opinion no miscarriage of justice has occurred. His Honour's reasons demonstrate that if he had addressed his mind to this question he would not have exercised his discretion to exclude the evidence. In my view, if this Court was asked to exercise that discretion, it should decline to do so.

In all the circumstances, therefore, in my opinion the appeal should be dismissed.