9.138 In DP 69, the Commissions raised an issue as to the admission under the uniform Evidence Acts of expert opinion evidence on the behaviour and development of children. The issue raised has two aspects: first, whether such evidence is admissible under the Acts; second, whether more needs to be done to encourage the admission of such evidence in appropriate circumstances.
The need for expert opinion evidence
9.139 Expert opinion evidence on the development and behaviour of children can be relevant to a range of matters in legal proceedings, including testimonial capacity, a fact in issue (for example, the inferences to be drawn from evidence of the behaviour of a child towards a person alleged to have assaulted the child), the credibility of a child witness, the beliefs and perceptions held by a child, and the reasonableness of those beliefs and perceptions. There is a concern that, for a number of reasons, such evidence is not being received as frequently as it should be.
9.140 The ALRC and the Human Rights and Equal Opportunity Commission (HREOC), in their 1997 Report, Seen and Heard: Priority for Children in the Legal Process, identified a traditional belief, based on preconceptions about the capacity of children to remember and recall events accurately, that children’s evidence is unreliable. The ALRC and HREOC concluded that these preconceptions are often inaccurate. There is growing psychological research, for instance, demonstrating that even very young children are capable of giving reliable evidence. It was also concluded that unsatisfactory legal outcomes follow from these preconceptions.
9.141 In order to overcome the problem of potential misconceptions about children, the ALRC and HREOC recommended that expert opinion evidence on issues affecting the assessment of child witness reliability should be admissible in any civil or criminal proceeding in which abuse of that child is alleged. Particular emphasis was given to evidence that might assist the decision maker in understanding ‘the patterns of children’s disclosure in abuse cases or the effects of abuse on children’s behaviour and demeanour in and out of court’. In order to achieve this, the ALRC and HREOC recommended that the opinion and credibility rules be modified. The Royal Commission into the NSW Police Service (the Wood Royal Commission) supported this recommendation.
9.142 The New South Wales Legislative Council Standing Committee on Law and Justice recommended, in its 2002 report on child sexual assault prosecutions, that the Evidence Act 1995 (NSW) be amended to permit, in child sexual assault proceedings, the admission of expert evidence relating to child development (including memory development) and the behaviour of child victims of sexual assault, along the lines of s 79A of the Evidence Act 2001 (Tas).
9.143 Like Tasmania, Queensland and New Zealand have enacted legislative provisions that at least partially address the issue of the admissibility of expert evidence regarding the assessment of the credibility or reliability of child witnesses.
Barriers to admission of expert opinion
Relevance and the common knowledge rule
9.144 At common law, Australian courts have at times demonstrated a reluctance to admit expert opinion evidence of typical patterns of behaviour and responses of child victims of abuse. There is a tendency to exclude expert evidence about the behaviour of child victims because it is considered to be within the ordinary experience of the jury. Australian courts operating under the common law opinion rule are likely to continue being cautious in admitting expert evidence regarding patterns of behaviour in child abuse victims, although South Australian and Canadian courts have allowed the admission of expert evidence concerning child witnesses.
9.145 In some respects, the admission of expert opinion evidence in relation to the development and behaviour of children should be easier under the uniform Evidence Acts. The requirements in relation to expert opinion evidence are less stringent than at common law. Under the uniform Evidence Acts, expert opinion evidence on child development and behaviour and the effects abuse has on those processes must be shown to derive from specialised knowledge of the expert based on that person’s training, study or experience. The expert opinion must be wholly or substantially based on that knowledge. Admission of such evidence is theoretically simplified by the abolition in s 80 of the common knowledge rule. Unfortunately, such evidence is still excluded in some cases as ‘unnecessary’.
The credibility rule
9.146 As noted above, expert opinion evidence of the development and behaviour of children can be relevant to the credibility of a child witness. Such evidence can assist the tribunal of fact in assessing the reliability of the witness. It can also prevent the tribunal of fact drawing inappropriate inferences from the behaviour of the witness either in giving evidence or in the factual circumstances of the case.
9.147 Where expert opinion evidence is tendered for this purpose it must not only satisfy the requirements of Part 3.3, it must also satisfy the credibility provisions in Part 3.7. The provisions of Part 3.7 pose a significant obstacle to the admission of this type of evidence. As currently formulated, there are limited circumstances in which evidence relevant to the credibility of one witness can be led in chief from another witness. Evidence cannot be led by a party to ‘bolster’ the credit of the party’s own witness. Evidence sought to be led to challenge the credibility of the witness must fall within one of the categories set out in s 106. Further, such evidence must be put to the witness in cross-examination and denied. It is highly unlikely that counsel would ever be able to lead expert opinion evidence on the development and behaviour of children that goes to the level of development of a particular child, or to possible psychological explanations of the behaviour of the particular child. Evidence to reestablish the credit of a witness may only be led from the witness in re-examination, or, in certain circumstances, in the form of evidence of a prior consistent statement.
9.148 The Evidence Act 2001 (Tas) departs from the other uniform Evidence Acts by including an additional provision in s 79A specifically relating to experts in child development and behaviour. Section 79A provides:
A person who has specialised knowledge of child behaviour based on the person’s training, study or experience (including specialised knowledge of the impact of sexual abuse on children and their behaviour during and following the abuse) may, where relevant, give evidence in proceedings against a person charged with a sexual offence against a child who, at the time of the alleged offence, had not attained the age of 17 years, in relation to one or more of the following matters:
(a) child development and behaviour generally;
(b) child development and behaviour if the child has had a sexual offence, or any offence similar in nature to a sexual offence, committed against him or her.
9.149 This provision clearly seeks to overcome, for certain criminal proceedings, the traditional reluctance to accept that child development and behaviour is a subject of specialised knowledge and that expert opinion evidence is admissible on the topic. However, the provision does not expressly address the credibility rule.
9.150 The question was asked in IP 28 whether the Evidence Act 1995 (Cth) should be amended to allow clearly for the admission of expert evidence regarding the credibility or reliability of child witnesses and, if so, whether s 79A of the Evidence Act 2001 (Tas) is the appropriate model. The Commissions in DP 69 proposed that such an amendment should be made, using a modified form of the Tasmanian provision. The proposal was advanced together with a proposal to create an exception to the credibility rule for expert opinion evidence.
Submissions and consultations
Support for the proposal
9.151 The NSW DPP supports the Discussion Paper proposal, Proposal 8–1, noting the recommendation of the New South Wales Legislative Council Standing Committee on Law and Justice referred to above. Victoria Police supports Proposal 8–1, saying that it is ‘imperative that juries and the court’ have this information, particularly when considering the evidence of children in matters involving sexual assault. The need to overcome stereotypical perceptions of children is cited as a reason for adopting the proposal; so is the need to ‘rectify gaps and misunderstanding in allegedly common or general knowledge’ about child development and behaviour.
9.152 While supporting Proposal 8–1, two sexual assault counsellors nevertheless note their concern that increased reliance on expert opinion evidence relating to child development and behaviour could lead to ‘expert wars’. Similarly, the Litigation Law and Practice Committee of the New South Wales Law Society supports Proposal 8–1, but says that experience shows that, in matters involving expert evidence on psychological issues, questions can arise whether the expert has training, study or experience on the relevant field of expertise, and whether that training, study or experience furnishes evidence of ‘substance that can be assessed by the [tribunal] of fact’. 
Opposition to the proposal
9.153 On the other hand, the New South Wales Law Society’s Criminal Law Committee opposes Proposal 8–1 on the basis that s 79 sufficiently caters for admission of expert opinion evidence on child development and behaviour. The Criminal Law Review Division of the New South Wales Attorney General’s Department holds the same view, and sees the real issue as being the need for an exception to the credibility rule. In that respect, the Division supports Proposal 11–6.
9.154 The NSW PDO is ‘strongly opposed’ to the proposal. Support is expressed for leaving credibility to the tribunal of fact ‘untainted by an expert’s opinions’. Questions are posed. Will the accused be permitted to call expert evidence that children lie? Is it conceivable that expert evidence would be permitted to the effect that falsely accused people sometimes give false accounts to police in order to bolster a just cause? Reference is also made to experience under the uniform Evidence Acts.
Public Defenders have had experience of both successful and unsuccessful attempts by the Crown to call this sort of evidence under the [New South Wales] Evidence Act as it stands. There are many difficulties with this sort of evidence. Doctors and counsellors who have treated alleged victims of sexual assault naturally regard it as part of their role to support the alleged victim. Many of them have a deeply felt but mistaken conviction that alleged victims of sexual assault never lie. There is a tendency of such witnesses to treat every conceivable response of the complainant as being a ‘normal’ response of a victim of sexual assault. Thus immediate complaint is a ‘normal’ response, but so is not making a complaint for 20 years.
The Commissions’ view
9.155 In the Commissions’ view expert opinion evidence on child development and behaviour (including the effects of sexual abuse on the development and behaviour of children) can in certain cases be important evidence in assisting the tribunal of fact to assess other evidence or to prevent inappropriate reasoning processes based on misconceived notions about children and their behaviour.
9.156 There is scope within s 79 as it currently stands for the admission of expert opinion evidence on child development and behaviour. However, submissions received and consultations held by the Commissions demonstrate that Australian courts continue to demonstrate a reluctance to admit such evidence under s 79. Therefore, the Commissions conclude that s 79 should be amended to clarify the position. The Commissions do not see the recommended reform as constituting any major departure from the existing law, but as highlighting the admissibility of a particular type of expert opinion evidence.
9.157 There is some danger in admitting this category of evidence. In particular, the evidence might invite a jury to reason using the doubtful syllogism: abuse of children elicits certain behavioural responses; the complainant exhibited some or all those behaviours; therefore, the complainant is likely to be telling the truth about being sexually abused, or is likely to have been sexually abused, or was sexually abused. The reasoning is doubtful for several reasons. However, the dangers of such expert opinion evidence being misused can be addressed adequately by judicial comments or directions and the application of Part 3.11.
Drafting the proposed amendment
9.158 In drafting an amendment to s 79, the terms of s 79A of the Evidence Act 2001 (Tas) provide the Commissions with a starting point. As the credibility issue is dealt with elsewhere in the Report (see Chapter 12), the Commissions have opted for a simplified approach. The proposed provision is set out in Appendix 1.
Recommendation 9–1 Section 79 of the uniform Evidence Acts should be amended to provide that, to avoid doubt, the provision applies to evidence of a person who has specialised knowledge of child development and behaviour (including specialised knowledge of the effect of sexual abuse on children and of their behaviour during and following the abuse), being evidence in relation to either or both of the following:
(a) the development and behaviour of children generally;
(b) the development and behaviour of children who have been the victims of sexual offences, or offences similar to sexual offences.
 Australian Law Reform Commission and Human Rights and Equal Opportunity Commission, Seen and Heard: Priority for Children in the Legal Process, ALRC 84 (1997), Ch 14.
 Ibid, [14.15]–[14.25].
 A Ligertwood, Australian Evidence (4th ed, 2004), [7.30].
 Australian Law Reform Commission and Human Rights and Equal Opportunity Commission, Seen and Heard: Priority for Children in the Legal Process, ALRC 84 (1997), [14.15]–[14.25].
 Ibid, Rec 101.
 Ibid, [14.77].
 Royal Commission into the New South Wales Police Service, Final Report, vol 5 (1997), [15.131].
 New South Wales Legislative Council Standing Committee on Law and Justice, Report on Child Sexual Assault Prosecutions, Report 22 (2002), Rec 21. See the discussion of the Tasmanian provision below.
Evidence Act 1977 (Qld) s 9C(2). Expert evidence is admissible about the child’s level of intelligence, including their powers of perception, memory and expression, or another matter relevant to their competence to give evidence, competence to give evidence on oath, or ability to give reliable evidence. See, eg, R v D (2003) 141 A Crim R 471.
Evidence Act 1908 (NZ) ss 23C, 23G. Expert evidence is admissible in child sexual abuse cases on issues including the child’s mental capacity, intellectual impairment, and emotional maturity; the general development level of a child the same age; and the degree of consistency of evidence about the child’s behaviour with the behaviour of sexually abused children of the same age: see, eg, R v M  NZFLR 151.
 Queensland Law Reform Commission, The Receipt of Evidence by Queensland Courts: The Evidence of Children, Report No 55: Part 2 (2000), Ch 15.
 See, eg, Ingles v The Queen (Unreported, Tasmanian Court of Criminal Appeal, Green CJ, Crawford and Zeeman JJ, 4 May 1993); R v Venning (1997) 17 SR(WA) 261; F v The Queen (1995) 83 A Crim R 502.
 See I Freckelton and H Selby, Expert Evidence: Law, Practice, Procedure and Advocacy (2nd ed, 2002), 363–371.
 In C v The Queen  SASC 4095, King CJ at  stated that expert evidence regarding the behaviour of child sexual abuse victims may be admissible where that behaviour is ‘so special and so outside ordinary experience that the knowledge of experts should be made available to courts and juries’.
 Expert evidence of the typical patterns of behaviour of child sexual abuse victims may be admitted to assist the jury in their decision where they might otherwise, using their common knowledge and sense, draw an adverse inference against the child witness due to their behaviour: see, eg, R v J (FE) (1990) 74 CR (3d) 269; R v RAC (1990) 57 CCC 3d 522.
 As a result of Uniform Evidence Acts s 102.
 The failure of evidence to fall within one of these defined categories was the reason cited by Gaudron J in HG v The Queen (1999) 197 CLR 414 for holding that opinion evidence of a psychologist regarding a child complainant was in that case inadmissible.
 Uniform Evidence Acts s 108. See the discussion in Ch 12.
 Australian Law Reform Commission, Review of the Evidence Act 1995, IP 28 (2004), Q 6–9.
 Australian Law Reform Commission, New South Wales Law Reform Commission and Victorian Law Reform Commission, Review of the Uniform Evidence Acts, ALRC DP 69, NSWLRC DP 47, VLRC DP (2005), Proposal 8–1.
 Ibid, Proposal 11–6.
 Director of Public Prosecutions (NSW), Submission E 87, 16 September 2005.
 Victoria Police, Submission E 111, 30 September 2005.
 R Shackel, Submission E 105, 27 September 2005.
 K Mack, Submission E 82, 16 September 2005.
 Rosemount Youth and Family Services, Submission E 107, 15 September 2005.
 The Criminal Law Committee and the Litigation Law and Practice Committee of the Law Society of New South Wales, Submission E 103, 22 September 2005.
 NSW Attorney General’s Department Criminal Law Review Division, Submission E 95, 21 September 2005.
 New South Wales Public Defenders Office, Submission E 89, 19 September 2005.
 J Dowsett and F Feld, ‘Opinion Evidence’ (Paper presented at Evidence Acts Review Workshop for the Judiciary, Sydney, 30 April 2005).