Medical evidence comment
Dr Min Lo and Dr Clare Healy on behalf of Doctors for Sexual Abuse Care, comment on a case covered in LawTalk 753, 28 June 2010 and Warren Pyke’s commentary on medical evidence in sexual offence cases. They say:
What may not have emerged from the commentary are several important points.
In Tuhura v The Queen  NZCA 246 (10 June 2010) the attending doctor was impermissibly asked at trial to express an opinion as to whether the injuries sustained by the complainant were more likely to be due to non-consenting sexual intercourse. Unfortunately the trial judge did not disallow the question.
In the Court of Appeal, Dr Healy described at  as “a DSAC doctor of considerable experience” gave expert evidence for the defence that “it has not been found possible to identify clinical findings which would be accurate and reliable indicators that vaginal and/or anal penetration was non-consensual as opposed to consensual” and that “It is not possible to comment on the presence or absence of consent based on the injuries in this case”.
This expert evidence, accepted by the Court of Appeal, was a re-statement of similar expert evidence relied on by that court in four of its decisions given in the period 2003 to 2008. In three of these cases, the expert opinion was provided by witnesses who are members of DSAC: R v A (Dr Carol Shand), R v Matenga (Dr Min Karen Lo) and R v Garraway (Dr Min Karen Lo).
It was against this background that the Court of Appeal at  stated that:
“It appears that the prosecutors, defence counsel and the Judge were unaware of those cases - if any of them had been aware of them, we doubt that the doctor would have been asked for her views on the issue of consent. In cases where the injuries suffered by the complainant are not such that a doctor can properly express a view as to whether the sexual contact prior to the injuries being incurred was consensual or not, the doctor should not be asked to express a view. If the question is asked, the response should indicate that he or she cannot properly express a view one way or the other.”
The problem, it would seem, is that some trial lawyers are unaware of the limitations to medical opinion evidence in sexual offence cases. Whether or not genital injuries are sustained during a sexual encounter, are a result of the individual’s characteristics and case specific circumstances. These factors include the victim’s age, their general health, medications, skin condition, the situational factors including, amount of force applied or the use of a foreign body etc. The genital tissue is elastic, the likelihood of sustaining a genital injury during sexual contact (whether consenting or non-consenting) is small and most victims seen after an alleged sexual assault will have a normal genital examination. Counsel should understand that simply agreeing or not agreeing to a sexual act is an oversimplification of the likelihood of sustaining injury. In the majority of cases, regardless of the extent of injury (small or otherwise), doctors should not be asked whether the sexual act was more likely to be non-consenting than consenting. There is no medical literature or research to answer this question. Unfortunately, this has not been sufficiently disseminated amongst prosecuting lawyers, defence counsel, judges and some doctors.
DSAC has taken this approach for many years and as can be seen when senior members of DSAC, acting in their role as expert witnesses, have contributed to the Court of Appeal rulings which have set the standard for soliciting opinions from medical witnesses in sexual offence trials.
This article was published in LawTalk 755, 2 August 2010, page 10.