Duckett v The King

SUPREME COURT OF SOUTH AUSTRALIA
(Court of Appeal: Criminal)
DUCKETT v THE KING
[2025] SASCA 44
Judgment of the Court of Appeal
(The Honourable Chief Justice Kourakis, the Honourable Justice S Doyle and the Honourable Justice Bleby)
17 April 2025
APPEAL AND NEW TRIAL - APPEAL - GENERAL PRINCIPLES
CRIMINAL LAW - PROCEDURE - VERDICT - ALTERNATIVE VERDICTS - DIRECTIONS TO JURY
CRIMINAL LAW - EVIDENCE - OPINION EVIDENCE - EXPERT OPINION
Application for permission to appeal against conviction.

The applicant was charged with two counts of rape contrary to s 48 of the Criminal Law Consolidation Act 1935 (SA) and one count of attempted murder. The prosecution case was that in the early hours of 16 June 2022, the applicant attacked the complainant near the stairs between the Festival Centre and the River Torrens. A jury by majority found the applicant guilty of one count of rape. The jury unanimously acquitted the applicant of the charge of attempted murder and of a second charge of rape.
The applicant raised two issues on appeal:
1.whether the trial judge erred by failing to leave an alternative verdict of attempted rape; and
2.whether the judge erred by admitting evidence of a forensic nurse from Yarrow Place Rape and Sexual Assault Service.
Held (by the Court) granting leave to appeal but dismissing the appeal:
1.A verdict of attempted rape was not reasonably open on the evidence.
2.The forensic nurse gave clear evidence of the factual foundation of her expert opinion evidence.
3.The forensic nurse engaged in a process of reasoning sufficient to demonstrate that her expert opinion was based substantially within a field of specialised knowledge.

Criminal Law Consolidation Act 1935 (SA) (SA) ss 5, 48; Criminal Procedure Act 1921 (SA) s 140; Juries Act 1927 (SA) s 57, referred to.
R v Perdikoyiannis (2003) 86 SASR 262; R v Winner (1989) 39 A Crim R 180; R v Tilley (2009) 105 SASR 306; R v Trewartha (2001) 123 A Crim R 259; Dasreef Pty Ltd v Hawchar (2011) 243 CLR 588; Makita (Aust) Pty Ltd v Sprowles (2001) 52 NSWLR 705; Lang v The Queen (2023) 278 CLR 323, considered.

DUCKETT v THE KING
[2025] SASCA 44
Court of Appeal – Criminal: Kourakis CJ, Doyle and Bleby JJA

THE COURT: The applicant was charged with two counts of rape contrary to s 48 of the Criminal Law Consolidation Act 1935 (SA) (‘CLCA’) (Counts 1 and 3) and one count of attempted murder (Count 2). A jury found the applicant guilty, by majority, of one count of rape, being Count 1 on the Information. The jury unanimously acquitted the applicant of the charge of attempted murder and the charge of rape the subject of Count 3.
The application for permission to appeal raises two issues. The first is whether the trial judge erred by failing to leave an alternative verdict of attempted rape. The second is whether the judge erred by admitting evidence of a forensic nurse from Yarrow Place Rape and Sexual Assault Service. The applicant contended that the witness did not establish a specialised knowledge that supported her opinion about the potential causes of the complainant’s injuries and that there was no factual foundation for that opinion.
Background
The prosecution case was that in the early hours of 16 June 2022, the complainant was attacked by an assailant, later identified as the applicant, on the banks of the River Torrens. The attack occurred near the stairs located between the Festival Centre and the River Torrens, adjacent to the footbridge to Adelaide Oval.
Earlier in the evening, the applicant and his companion, Mr Mondin, had been in the Adelaide CBD, walking around and drinking. Mr Mondin, who was called as a witness by the prosecution at trial, gave evidence that he and the applicant had been to McDonalds on Hindley Street. They then walked to Bank Street. The applicant first met the complainant near the Strathmore Hotel. Prior to meeting the applicant, the complainant had also been drinking. The applicant and complainant had not met before this encounter and were not known to each other.
The complainant, the applicant and Mr Mondin began talking. The complainant asked for a cigarette. She had some of their alcohol. Mr Mondin described the interaction between the complainant and the applicant as involving ‘sweet talk’. The complainant, applicant and Mr Mondin began walking, as a group, towards the Adelaide Railway Station. They walked through the plaza and towards the Festival Centre. They went down the stairs through the gap between the Festival Centre and the Dunstan Playhouse. At this stage, both the complainant and Mr Mondin described the applicant as behaving strangely.
The group lingered for some time at a set of stairs near the Festival Centre. Mr Mondin and the applicant each had a cask of wine. The group kept drinking. The complainant supplied the two men with oxazepam and consumed some herself. At this point, the group was having a good time. Mr Mondin gave evidence that at some point he went for a walk as he ‘didn’t want to be a third wheel’. He said that as he was walking away, he saw the applicant and the complainant embracing and getting close.
The complainant gave evidence that after Mr Mondin left, the applicant asked the complainant for sex. The complainant refused. The applicant then became aggressive. He began pushing her to a corner near the stairs and forcefully removed her pants and underwear. He pinned the complainant down. The complainant was screaming and resisting the assault. The complainant’s evidence was that the applicant then forced his penis inside her vagina. This was the subject of Count 1. At numerous times when giving evidence, the complainant explained the applicant said to her ‘gee you’re very tight down there’. The applicant then placed his finger into the complainant’s vagina. The applicant said ‘I’ve got to loosen you up’. This act of digital penetration was not charged.
The complainant said that she managed to free herself, put her pants back on and try to run away, towards the stairs. She said the applicant told her ‘You’re not going nowhere’. The applicant then dragged her by her hair back to the corner. The complainant said that the applicant proceeded to rip off her clothing again and rape her by inserting his penis into her vagina for the second time. This was the subject of Count 3.
At some point, the applicant threatened to kill the complainant. The complainant said that the applicant was strangling her and hitting her head on the cement in the corner. She said the applicant told her ‘I’m going to kill you if you keep making noise, I’ll snap your neck’. She demonstrated how the applicant held her head to one side and twisted it. This was the subject of Count 2, the charge of attempted murder.
Mr Mondin was absent for some time but returned because he had misplaced his cask of wine. He gave evidence that he returned to the stairwell to see how much alcohol the applicant had. On his return to the stairwell, he said he heard a moaning-type noise which sounded like someone was in pain. He observed the applicant holding the complainant down. He described the applicant standing over the complainant, pinning her down and twisting her arms. The complainant started saying ‘help’. At one stage, the applicant punched the complainant. Mr Mondin described the complainant as ‘shaken’ as she had just been attacked.
Mr Mondin was asked about the state of dress of the applicant and complainant when he found them. He said:
As far as I know, they were dressed but I wasn’t worried about what – I don’t know. I wasn’t there so I don’t know what was happening. But my priority was to separate them but as far as dress, I – I guess you could say partially clothed, fully clothed, I’m not sure. It was – that’s the starting spot, all I seen was the arms.
Mr Mondin was asked again in cross-examination about whether the applicant and complainant were clothed when he saw them. He said, ‘No, I seen her arms to be honest’. He was then asked if he saw anything that would suggest they were undressed. He said:
It happened very quickly. If they were undressed, they were pulled up very quickly.
Mr Mondin was cross-examined on his statement to police, in which he said, ‘I believed they were both dressed [at the time]’, which he acknowledged was his ‘understanding’. He also accepted that he said to police, ‘If I didn’t turn up when I did, she would’ve been either seriously assaulted or worse’.
Mr Mondin intervened and stood between the applicant and the complainant. He attempted to calm the complainant down before leaving her by some streetlights. The complainant gave evidence that Mr Mondin walked her to the Adelaide Railway Station. She encountered and had a conversation with a ticket inspector, Mr Remanan.
The applicant’s counsel suggested to the complainant in cross-examination that she had told Mr Remanan that someone had ‘tried’ to rape her, not that she had been raped. The complainant denied that she had said someone had tried to rape her and said she told Mr Remanan that she had been raped.
Mr Remanan gave evidence of an initial complaint by the complainant. He had body-worn footage of some of the interaction and made contemporaneous notes of his conversation with the complainant. His body-worn footage was tendered. Having made reference to his notes, Mr Remanan gave evidence that the complainant had told him that ‘This guy was trying to rape me and everything’.
The complainant was taken to hospital and then to Yarrow Place Rape and Sexual Assault Service for a forensic examination. The forensic examination occurred about 56 hours after the events. The complainant was examined by a registered nurse, Ms Markham. Ms Markham observed injuries to the complainant’s neck and left hand. She also described abrasions under the clitoral hood and redness of the skin in the vaginal area. She estimated that genital abrasions usually heal within five days but explained that it was not possible to age the injury more specifically than saying it was ‘fairly recent’.
Ms Markham said that the abrasions under the clitoral hood were consistent with the complainant’s account. She said that these injuries could be caused by an object like a penis or finger moving forcefully across the surface of the skin. She could not say that this was the only possible cause of that type of injury.
Ms Markham’s examination of the complainant included taking swabs from the complainant’s genital area and other areas of her body. No seminal fluid was discovered following these swabs. No sperm was detected from the genital swabs. She conducted an internal vaginal examination but observed no injuries.
Several of the swabs were sent to Forensic Science South Australia for DNA testing. Ms Koch, a forensic scientist, confirmed a presumptive positive reaction for the presence of seminal fluid on the inner crutch area of the complainant’s underpants. Low or very low amounts of sperm were observed on three of the cuttings of the complainant’s underpants. The hypothesis did not support the applicant being a contributor to the DNA profile that was found on these cuttings. There was moderate support for the presence of the applicant’s DNA on a swab from the complainant’s neck and tape lift from the waistband of her pants.
The defence case was that the rape the subject of counts 1 and 3 did not occur. The defence did not challenge Mr Mondin’s evidence of what he saw when he returned to the stairwell or the complainant’s evidence that she was subjected to a violent physical assault. The defence challenged the evidence of the assaults insofar as they were said to be life threatening.
The appeal
Whether the primary judge erred in failing to leave the alternative verdict of attempted rape on Count 1
Section 140 of the Criminal Procedure Act 1921 (SA) (‘CPA’) provides:
140—Verdict for attempt where full offence charged
If on the trial of a person charged with any offence it appears to the jury on the evidence that the defendant did not complete the offence charged but that the person was guilty only of an attempt to commit the offence—
(a) the jury may return as their verdict that the defendant is guilty of an attempt to commit the offence charged; and
(b) in that case—the defendant will be liable to be punished in the same manner as if the defendant had been convicted on an information for such an attempt.
The respondent accepted that, as with the duty at common law, s 140 implicitly burdens a trial judge with the duty to direct the jury as to the existence of the power in an appropriate case.[1] As to this, s 57(3)(a) of the Juries Act 1927 (SA) provides:
(3)Where an accused person is charged with a particular offence (the major offence) and it is possible for a jury to return a verdict of not guilty of the offence charged but guilty of some other offence for which the person has not been charged (the alternative offence)—
(a) the jury must consider whether the accused is guilty of the major offence before considering whether he or she is guilty of the alternative offence; …
[1] Referring to, among other cases, R v Perdikoyiannis (2003) 86 SASR 262 at [36]-[39] (Doyle CJ, Besanko and Sulan JJ agreeing).
In R v Perdikoyiannis,[2] Doyle CJ (Besanko and Sulan JJ agreeing) observed that the circumstances in which an alternative and lesser count, not appearing on an information, may be left to the jury were limited,[3] adopting the statement by the New South Wales Court of Criminal Appeal in R v Winner:[4]
[S]uch a verdict may only be returned if each element of the lesser offence of which the accused is convicted, is also an element of the greater offence with which he was charged, and has been alleged against him either expressly or by necessary implication in the indictment.
[2] (2003) 86 SASR 262.
[3] R v Perdikoyiannis (2003) 86 SASR 262 at [43].
[4] (1989) 39 A Crim R 180 at 181.
Section 140 of the CPA overcomes this limitation insofar as attempts are concerned, as not all the elements of an attempt are included in the substantive offence. Section 57(3) of the Juries Act then requires a direction that the jury first consider the major offence before considering an alternative verdict of attempt, where that is available by reason of s 140, in addition to alternatives available at common law.
The question is then when it is appropriate to leave an alternative offence of an attempt to commit the primary offence charged. In R v Tilley, the Court of Criminal Appeal described the effect of the authorities:[5]
In short, at common law, taking into account s 57(3) of the Juries Act, the following propositions emerge from the case law. Merely because an alternative verdict may theoretically be open or possible in the broadest sense, this is not enough to require an alternative verdict to be left. It must be a “reasonably open” or “fairly and practically open” or a “viable rational result” on the evidence before the jury. The duty to put an alternative verdict lies with the trial judge, regardless of whether or not the prosecution or defence raise the issue. Thirdly, the putting of an alternative verdict to the jury must not result in a miscarriage of justice.
[5] R v Tilley (2009) 105 SASR 306 at [60] (Bleby, Gray and Layton JJ).
Whether to leave an alternative verdict requires a practical judgment, ‘having regard to the issues actually raised, and to the findings or verdicts open as a matter of law and fairly or practically open on the facts’.[6]
[6] R v Trewartha (2001) 123 A Crim R 259 at [36].
The applicant relied on the following evidence as demonstrating that the alternative verdict of attempted rape on Count 1 was reasonably open. First, on the complainant’s evidence, the applicant made the comments that the complainant was ‘tight’ and that he had to ‘loosen [her] up’ after the first particularised act of penile rape and before the uncharged act of digital penetration. The applicant submitted that it was reasonable to infer from these comments that penetration was unsuccessful, hence the introduction of his finger. At the very least, it left open the possibility that penetration was unsuccessful.
The applicant also relied on several other matters. The complainant had been drinking heavily and was intoxicated. The applicant submitted that this compromised her credibility and reliability such that the jury could not be satisfied that an act of penetration occurred.
Next, Mr Remanan gave evidence that the complainant said the applicant was trying to rape her. This evidence was relevant to the reliability of the applicant’s account in evidence that she was raped.
The applicant also relied on the absence of injuries or seminal fluid located on the higher or lower vaginal swabs, taken within several days of the attack. He accepted that penetration may not result in the deposit of seminal fluid but submitted that its absence was a significant feature that cast doubt on the complainant’s evidence that penetration occurred. The swab from the complainant’s underwear that did indicate the presence of seminal fluid could not be linked to the applicant.
The applicant also relied on the evidence of Mr Mondin, related above, as to the state of undress in which he found the complainant on his return. Mr Mondin demonstrated a state of uncertainty on this, but said he thought they were partially or fully clothed, or that if they had been undressed, ‘they were pulled up very quickly’. As the applicant submitted this was direct evidence of the assault the subject of Count 3, not Count 1.
The applicant submitted that this account made it less probable that the attack the subject of Count 1 amounted to a rape. That is, it made it improbable that the complainant was unclothed any stage.
This evidence must be considered in its full context. In respect of the first rape, the complainant gave evidence that the applicant ‘had his penis in my private’. She said she was trying to hold onto her tracksuit pants, ‘but he was that strong, he ripped it off of me’. She said they came all the way off. She said that after the assault the subject of Count 2, she got away, grabbed her clothing and put it on. The applicant grabbed her hair and said, ‘Where do you think you’re going? You’re not going nowhere’. He twisted her arm, and she went back to the corner with him, where ‘he started raping [her] again’.
As to the complainant’s clothing at the point of this second rape, the complainant said that the applicant ‘ripped it off again’. She said he was positioned ‘on top of me when I had my tracksuit pants on’. This evidence contains an internal inconsistency, which was relevant to the complainant’s reliability as a narrator. Nonetheless, there was evidence on the complainant’s account that she had retrieved her clothing between the first and second rapes. This was pursued in cross-examination as follows:
Q.Now at some point you got away.
A.Yes, I did.
Q.And he chased you to the stairs.
A.Yes, I ran.
Q.When you ran to the stairs, did you have all your clothes on again.
A.I grabbed them and I put it on me real quick.
Q.So -
A.He wanted to have a look to see if anyone was coming.
Q.So you grabbed your tights and put them back on.
A.Yes.
Q.And you grabbed your tracksuit pants and put them back on.
A.Yes. I put them on and I ran.
Q.Sorry.
A.I put them on, ran to the stairs.
Q.And how long did it take you to put your tights back on.
A.I don’t know. I just - I don’t know.
Q.Do you recall.
A.This was all fast.
Q.Do you recall where he was when you were putting your tights and your tracksuit pants back on.
A.He got up and to have a look, see if anyone was coming.
Q.He got up, did he.
A.He went to look.
Q.So is that how you were able to get away.
A.Well, he got up.
Q.Didn’t you say on Wednesday that you couldn’t remember how you were able to get away.
A.Yes, I did say that.
Q.But now you’re saying he got up to look to see if anyone was around.
A.Sure - I’m sure he heard - he was - he was checking seeing if anyone was coming. That’s what I mean.

Later in cross-examination, the complainant said that the applicant took off her tracksuit pants and tights again for the second rape. Subsequently, however, she said that when ‘the big man’ (Mr Mondin) came back, she had her pants on. Again, there was internal inconsistency in her evidence with respect to her state of dress at the time of the events the subject of Count 3.
The applicant submitted ‘the real issue’ was whether the complainant was a reliable narrator with respect to all events that occurred over the course of the admitted assault. He submitted that in all of the circumstances of this evidence, it was open to return a verdict of attempted rape in respect of Count 1.
The complainant’s argument hinged in large part, therefore, on the attacks that were clearly available on the complainant’s reliability. That raises the question of the evidential basis on which it could be said that the alternative verdict was reasonably open. As to this, the complainant relied mainly on the absence of internal injuries that would be consistent with a violent act of penetration. In this regard, s 5 of the CLCA defines sexual intercourse as including penetration of the labia majora, which may be only slight. The complainant was not specific as to the extent of penetration; in addition to the evidence referred to earlier, she said that the applicant ‘put his pee pee in my vagina, he said ‘Gee you’re tight’…’ and that he was hurting her.
The question is whether, in respect of Count 1, the evidence allowed for a reasonable hypothesis that the applicant had attempted to rape the complainant and not succeeded. That requires more than just a speculative or theoretical possibility. It may be accepted that there was a basis on which to impugn the complainant’s reliability generally. Having said that, the complainant’s inconsistencies in evidence with respect to her state of dress at the point of the events the subject of Count 3 do not provide evidential support for the reasonable possibility that Count 1 only amounted to an attempted rape.
The words attributed to the applicant, ‘gee you’re tight’, when considered with the complainant’s evidence of pain, provide an evidential foundation for penetration in addition to the complainant’s narrative evidence that she was penetrated. Further, notwithstanding the complainant’s own assessment of her intoxication, she remained adamant that she was penetrated. The challenge in cross-examination did not allow for, or produce evidence supporting, the possibility that the applicant had attempted, but not succeeded, in raping the complainant:
Q.The little man attacked you, didn’t he.
A.Yes, and he raped me.
Q.Well, I say he didn’t rape you. What happened was you thought he was going to but the big man came back.
A.He did rape me and he put his finger in my vagina and hurt me.
To allow for the possibility that the applicant only got so far as an attempt to rape the complainant in respect of Count 1 necessarily requires not just being satisfied that penetration did not occur, but filling what is otherwise an evidential gap as to what did occur. The doubt that the jury manifestly had in respect of Count 3 was relevant to their consideration of Count 1. However, it did not provide an evidential basis for a conclusion that what the complainant said was a completed rape was only an attempt.
Notwithstanding the obvious limitations in the complainant’s evidence, we cannot see that this evidential gap was filled. For that reason, we are not satisfied that a verdict of attempted rape was ‘reasonably open’ or ‘fairly and practically open’ or a ‘viable rational result’ on the evidence. We grant leave to appeal on Ground 1 but dismiss the appeal on this ground.
Whether the judge erred in admitting expert evidence of Ms Markham about the potential cause of the injuries to the complainant’s genitalia
Ms Markham gave evidence of her qualifications and experience on the voir dire and at trial. She was a registered nurse and held a Masters of Nurse Practitioner. She had qualifications in forensics, sexual health and women’s health. As part of her role at Yarrow Place, she completed a sexual assault nurse examiner course and various other courses relating to sexual assault and domestic violence. She received ongoing training as part of her role, keeping up to date with developments in the field.
Ms Markham’s role at Yarrow Place was to provide medical care to clients and conduct forensic examinations after a sexual assault. She had been performing that role since 2014. In that time, she had conducted around 500 forensic examinations and hundreds more of physical and genital examinations. She was experienced in preparing reports about her examinations, her findings and her ultimate opinion, and in giving evidence in court.
The applicant submitted that Ms Markham’s expert qualifications did not extend to her giving evidence as to the possible causes of the injury to the complainant’s genital area, which evidence we set out in full:
Q.Perhaps if I ask then can you say what could be a cause for an injury for the type of injury we see as to the genital area.
A.Yes. An object moving forcefully across the surface of the skin and that could be a finger, a penis or another object and that would be damaging the superficial layers of the skin.
Q.And, again, can you say that would be the only cause of an injury or the only possible cause of an injury that we’ve seen here.
A.No.
The applicant’s complaint had three elements. First, he submitted that there was no evidence that the likely or even possible causes of injury were a field of specialised knowledge. Second, he submitted that the prosecution did not establish an underlying factual foundation for Ms Markham’s opinion about the possible causes of injury to the complainant’s clitoral hood. Third, he submitted that notwithstanding Ms Markham’s qualifications and experience, at no point did she give evidence about her training or experience in identifying the causes of an injury of the nature she described.
It is convenient to address first the second of these complaints. In Dasreef Pty Ltd v Hawchar, Heydon J explained ‘the statement of reasoning rule’:[7]
At common law there is no doubt than an expert opinion is inadmissible unless the expert states in chief the reasoning by which the expert conclusion arrived at flows from the facts proved or assumed by the expert so as to reveal that the opinion is based on the expert’s expertise.
[7] Dasreef Pty Ltd v Hawchar (2011) 243 CLR 588 at [91].
The applicant submitted that Ms Markham’s opinion was based on a version of events that she took from the complainant during the examination. The complainant’s statements to Ms Markham were, of course, not before the jury. However, the applicant submitted that the prosecution did not put forward the relevant portions of the complainant’s evidence to establish the underlying factual foundation for Ms Markham’s opinion about the possible causes of injury.
Ms Markham gave evidence about her observations. She was asked about what she meant by ‘abrasion’. She said:
Abrasions are superficial injuries to the skin. Often caused by dragging force so either pressure and movement together of a blunt, sharp, or rough-edged object moving across the surface of the skin, damaging the superficial layers of the skin, but not penetrating the full thickness of the skin. So it’s usually just the first surface of the skin.
The evidence now under challenge, set out earlier, was preceded by Ms Markham describing the injury as ‘small abrasions under the clitoral hood’. It is clear enough, having regard to the totality of her evidence, that she gave evidence of her observation of superficial injuries to the surface of the skin. She then gave the challenged evidence as to how an abrasion may be caused.
With respect, then, to the challenge that there was an insufficient factual foundation established for Ms Markham’s opinion, Ms Markham gave clear evidence that she relied on her observations of the complainant’s injuries in forming her conclusion that the complainant had sustained abrasions to the clitoral hood and her conclusions as to the possible causes of those injuries.
The first and third complaints under this ground of appeal can be considered together. In Makita (Aust) Pty Ltd v Sprowles,[8] Heydon JA in the New South Wales Court of Appeal explained the conditions of admissibility of expert evidence:[9]
In short, if evidence tendered as expert opinion evidence is to be admissible, it must be agreed or demonstrated that there is a field of “specialised knowledge”; there must be an identified aspect of that field in which the witness demonstrates that by reason of specified training, study or experience, the witness has become an expert; the opinion proffered must be “wholly or substantially based on the witness’s expert knowledge”; so far as the opinion is based on facts “observed” by the expert, they must be identified and admissibly proved by the expert, and so far as the opinion is based on “assumed” or “accepted” facts, they must be identified and proved in some other way; it must be established that the facts on which the opinion is based form a proper foundation for it; and the opinion of an expert requires demonstration or examination of the scientific or other intellectual basis of the conclusions reached: that is, the expert’s evidence must explain how the field of “specialised knowledge” in which the witness is expert by reason of “training, study or experience”, and on which the opinion is “wholly or substantially based”, applies to the facts assumed or observed so as to produce the opinion propounded.
[8] (2001) 52 NSWLR 705.
[9] Makita (Aust) Pty Ltd v Sprowles (2001) 52 NSWLR 705 at [85].
In Lang v The Queen,[10] Kiefel CJ and Gageler J accepted the continuing applicability of these principles under the uniform evidence legislation and at common law. They explained what is necessary to show the application of specialised knowledge:[11]
Those principles require that, in order to satisfy the condition of admissibility that the opinion of an expert be demonstrated to be based on specialised knowledge or experience, the inference drawn by the expert which constitutes the opinion be supported by reasoning on the part of the expert sufficient to demonstrate that the opinion is the product of the application of the specialised knowledge of the expert to facts which the expert has observed or assumed.
(Emphasis added)
[10] (2023) 278 CLR 323.
[11] Lang v The Queen (2023) 278 CLR 323 at [11].
Their Honours went on to say:[12]
The requirement for the opinion to be demonstrated to be the product of the application of the specialised knowledge of the expert is not absolute. In the terminology of the uniform evidence legislation, it is enough that the opinion be demonstrated to be based substantially on that specialised knowledge. Expression of the requirement in terms of substantiality recognises that specialised knowledge cannot be wholly divorced from common or ordinary knowledge and that it is “the added ingredient of specialised knowledge to the expert’s body of general knowledge that equips the expert to give his or her opinion”. The requirement will not be contravened by a process of reasoning on the part of an expert which involves using only those parts of the common or ordinary knowledge of the expert that are necessary for the expert to use in forming his or her opinion through the application of specialised knowledge.
(Citations omitted; emphasis added)
[12] Lang v The Queen (2023) 278 CLR 323 at [12].
In the same case, Gordon and Edelman JJ explained that the expert witness must expose how their expertise is the ‘substantial basis connecting the factual foundation to the opinion given’.[13] This requires a ‘sufficient explanation of the connection in expertise between the factual foundation identified and the opinion of the expert’.[14] In this regard:[15]
“Sufficiency” is, however, an elastic concept. The extent of required explanation of how the opinion expressed is based upon expertise can vary and will involve issues of judgment. In some cases where expert evidence is given on a matter which is not in real dispute, the expert may not be required to expose in great detail the basis upon which the opinion is based on their expertise. But the more critical the opinion is to the matters in issue, and the more contested the opinion, the more necessary it will be that the opinion expose the expertise upon which it is based.
(Citations omitted)
[13] Lang v The Queen (2023) 278 CLR 323 at [223].
[14] Lang v The Queen (2023) 278 CLR 323 at [227].
[15] Lang v The Queen (2023) 278 CLR 323 at [228].
Finally, Jagot J referred to the observation in Dasreef[16] that in some cases, for example that of a specialist medical practitioner, it is not necessary to make explicit what matters of opinion are based wholly or substantially on the expert’s specialised knowledge:[17]
The point being made in Dasreef is that, while satisfaction of the requirement that an expert opinion must be based on the expert’s expertise determines the admissibility and not just the weight of the evidence, it is not necessarily the case that, if all matters underlying the opinion expressed are not “made explicit, it is not possible to be sure whether the opinion is based wholly or substantially on the expert’s specialised knowledge”.
(Citations omitted)
[16] Dasreef Pty Ltd v Hawchar (2011) 243 CLR 588 at [37].
[17] Lang v The Queen (2023) 278 CLR 323 at [434].
In the present case, Ms Markham gave no explicit evidence about her specialised knowledge in a field of causation of abrasive injuries to the female genital area. The evidence of her experience in conducting hundreds of forensic examinations and physical and genital examinations is described above.
Part of Ms Markham’s procedure in conducting forensic examinations was to obtain a summary of what the person describes happened to their body. In that regard, she explained:
The purpose of obtaining that summary is to help guide me on what medical care I can give to the patient, what forensic care I can give to the patient, where to potentially look for any injuries and also any photographs I may need to document and any aftercare.
Implicit in this evidence is experience of hundreds of cases where, in the course of her forensic examinations, Ms Markham obtained experience in observing injuries together with being given accounts of what occurred. That experience was combined with her training as a sexual assault nurse examiner and undertaking courses relating to sexual assault and domestic violence.
As the respondent submitted, the word ‘forensic’ in the description of her training and practice has significance. A forensic examination is undertaken for legal purposes which included the purposes of proving an offence. It is a necessary part of that function to look for abnormalities in presentation, as Ms Markham described, ‘looking at all areas of the skin to look for any injuries, bruises or abrasions or redness or anything sort of abnormal’, finishing with a genital examination. Consistently with this, she described taking histories and asking about areas of the body that might have been touched in different ways.
It is in that context of Ms Markham’s experience and training that she gave an opinion about possible causes of abrasions on the complainant’s genitalia. In Lang, the expert evidence under consideration was an opinion of a forensic pathologist that a wound was more likely to have been inflicted by another person. A majority of the Court held that this opinion evidence was admissible as it was based substantially on his specialised knowledge within the field of forensic pathology. Kiefel CJ and Gageler J emphasised a point touched on, but not elaborated, in Makita (Aust) Pty Ltd v Sprowles,[18] being the question of ‘whether a process of reasoning engaged in by an expert is sufficient to demonstrate that his or her opinion is the product of the application of specialised knowledge’.[19]
[18] (2001) 52 NSWLR 705.
[19] Lang v The Queen (2023) 278 CLR 323 at [15].
While some aspects of the forensic pathologist’s explanation in that case were not clearly communicated, it was ‘clear enough’ that he was saying that ‘he had engaged in a process of inductive reasoning which involved applying his knowledge of the interpretation of stab wounds to observed features of [the victim’s] wound to form a conclusion about which of the two scenarios was more likely’.[20] Kiefel CJ and Gageler J were unable to conclude that the forensic pathologist did other than draw on his specialised knowledge.[21]
[20] Lang v The Queen (2023) 278 CLR 323 at [21].
[21] Lang v The Queen (2023) 278 CLR 323 at [26].
The applicant sought to distinguish Lang on the basis that the forensic pathologist in that case had expertise beyond that of a registered nurse ‘because of the nature of [his] profession’. This was an unhelpful submission that, with respect, did not engage with and was implicitly dismissive of the considerable training and experience that qualified this expert witness in this case. Lang provides an exposition of principle. The relevant question is the applicability of that principle to the evidence of Ms Markham, having regard to her evidence of her training and experience, set out earlier.
The nature and length of Ms Markham’s experience, and in particular her practice in taking histories and examining patients in a sexual assault clinic, demonstrated that Ms Markham had extensive training with respect to, and considerable experience of, cases of sexual assault by penetration by a penis or a finger. There is sufficient evidence to conclude that her opinion as to causation was based substantially on her specialist knowledge of what may cause abrasions to female genitals.
It can also be accepted that this specialist knowledge was likely not the exclusive source of her opinion. As the respondent submitted, abrasions to human skin are to an extent within common human experience. So too is the fact that abrasions may be caused by dragging force. However, as Lang demonstrates, it was not necessary to establish that Ms Markham’s specialist knowledge was the sole source of her opinion about the possible causes of the abrasions.
We grant leave to appeal on Ground 2 but dismiss the appeal on this ground.
Conclusion
We grant leave to appeal on both Grounds 1 and 2 but dismiss the appeal.

[2025] SASCA 44

17 April 2025

Key Legal Topics

Areas of Law

Criminal Law

Evidence

Legal Concepts

Appeal

Charge

Expert Evidence

Sentencing