Speculation uncorroborated opinions and forensic expertise in child sex prosecutions

The High Court decision in HG v R (1999) 160 ALR 554 highlights a problematic form of expert evidence in child sex prosecutions. The Court strictly construed rape shield provisions to exclude evidence by a psychologist that a complainant was not sexually assaulted by the accused but had been assaulted some years before by her stepfather. More problematic, though, is the dalliance by some members of the Court with a notion that had apparently been repudiated in previous State and New Zealand decisions that there is a field of expertise that can diagnose whether sexual abuse has occurred from the behaviour of children subsequent to the alleged sexual assault. The most significant aspect of the decision, however, may be the preparedness by some members of the Court to construe the existence of expertise by reference to the processes by which expert opinions emerge from specialised knowledge within a discipline. Such an approach allows analysis of the substance and methods of a theory or area of expertise in order to determine whether a witness is themselves an expert. The down side of the approach is that it has the potential to proliferate forensic arguments about the legitimacy of expert areas of endeavour and about reasoning processes. The positive side is that it may promote expert witness accountably. © 1998 Taylor ‖ Francis Group, LLC.