Issued: 3 August 2022
An expert's evidence on a topic will not be admissible merely because they have read and reviewed the work of others on that topic. They must have their own qualifications (training, study or experience) before they can embark on presenting, verifying or adopting the views of others.
The expert's 'study' will be both their acquisition of academic qualifications and their critical review of relevant material.
AJ (the applicant) was convicted by a jury in the District Court of four sexual offences committed against two children and was sentenced to an aggregate term of imprisonment of eight years.
In the Court of Criminal Appeal, the applicant contended that the trial had miscarried as a result of the admission of inadmissible expert evidence from Dr Shackel. Dr Shackel, who has tertiary qualifications in psychology and law, authored a report on the behavioural and emotional responses of child victims to sexual abuse and patterns of offending behaviour by perpetrators. The report was tendered by the prosecutor over objection at trial. It cited numerous academic articles comparable to a 'literature review' as evidentiary support for the general opinions Dr Shackel expressed in both the report and her oral evidence.
The applicant sought leave to appeal against his conviction on a number of grounds, including that the evidence of Dr Shackel was wrongly admitted into evidence because she was not suitably qualified to provide the opinions she expressed.
The Court considered whether Dr Shackel had 'specialised knowledge based on training, study or experience' for the purpose of the exceptions to the opinion rule and the credibility rule provided in ss. 79 and 108 of the Evidence Act 1995 respectively, so as to enable her to give the evidence that she did.
Whilst Dr Shackel did not have clinical experience with child victims of sexual abuse, the combination of her qualifications in developmental psychology, her description of her own research into the behaviour and responses of victims, and her review of the work of others, meant that she had such specialised knowledge based on her 'study'. In addition, her opinions about the effect of that research and her endorsement of those opinions were wholly or substantially based on that specialised knowledge.
However, the Court did not accept that Dr Shackel had the requisite training, study or experience in relation to patterns of offending behaviour by perpetrators. She did not sufficiently demonstrate her research into this distinct topic, including speaking directly to offenders. Further, her analysis of other research that involved speaking to offenders, and reciting the effects of that research, was not sufficient to amount to 'study' on that topic.
The Court held that the wrongful admission of this second aspect of Dr Shackel's evidence constituted a miscarriage of justice as it was a 'wrong decision [on a] question of law' within the meaning of the Criminal Appeal Act 1912. The Court allowed the appeal, upholding this ground, quashing the applicant's conviction, and ordering a new trial.
When selecting an expert to give evidence, it is important to ensure that the expert has their own relevant qualifications in relation to all topics on which they are to give evidence.
In the field of psychology, an academic expert does not necessarily need to have direct clinical experience. However, merely reading and reviewing the work of others in relation to a certain topic is insufficient to establish specialised knowledge.
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