In Jones v Kaney the appellant sued a clinical psychologist, previously retained on his behalf as an expert witness, for negligence. The expert was retained in a personal injury proceedings relating to a road traffic accident in which the appellant suffered significant physical and psychiatric injuries including post traumatic stress disorder, depression and chronic pain syndrome.  

Relevantly, in the personal injury proceedings the judge ordered that the experts for both parties hold discussions and prepare a joint witness statement. The joint witness statement was damaging to the appellant’s claim and departed significantly from the respondent’s earlier assessments of his psychiatric condition. The respondent later admitted that the joint statement was drafted by the opposing expert and did not reflect what she had agreed during the expert discussions but notwithstanding this, the respondent signed the joint statement without amendment or comment. The appellant was denied permission to amend his expert evidence.  

In the negligence proceedings against the expert, the appellant argued that he was forced to settle his claim for significantly less that would have been achieved if the respondent had not negligently signed the joint statement. The expert did not dispute that the facts disclosed a good cause of action in negligence, rather the issue in dispute was whether she was shielded by immunity afforded to expert witnesses. The case was struck out at first instance, but was granted a ‘leapfrog’ certificate, on the basis that it involved a point of law of general public importance, enabling the matter to by-pass the Court of Appeal and go straight to the Supreme Court.

The decision

While the narrow issue on appeal was whether the act of preparing a joint witness statement was one in respect of which an expert witness enjoys immunity from suit, the submissions before the Court raised the broader issue of whether public policy justified conferring on an expert witness any immunity from liability in negligence in relation to the performance of his or her duties in that capacity. From the outset, Lord Phillips noted with surprise that the immunity had not been challenged in the past and that it had “simply been accepted” that a client was prevented from suing an expert in negligence. Despite the established history of the immunity, the starting point for the Court was that the onus rested “fairly and squarely” on the expert to justify the immunity she sought to shelter behind.  

Ultimately, the Court rejected the respondent’s two primary justifications for maintaining the immunity. The first was the ‘chilling effect’ of claims in negligence would have on expert witnesses, making them reluctant to give frank evidence or to provide expert evidence at all. It was held that there was “no justification” for an assumption that experts would be discouraged from providing their services if they could be sued and there was no empirical evidence either way to suggest that expert witnesses would not give frank evidence.

The second justification was that the immunity was necessary to ensure that expert witnesses complied with their paramount duty to the Court. The Court found that the abolition of the advocates’ immunity in the United Kingdom had not led to any diminution in advocates performing their duty to the Court and that it would be “mere conjecture” to assume it would be any different for expert witnesses.  

The decision was not unanimous though, with two out of the seven justices hearing the case dissenting. Both Lord Hope and Lady Hale were concerned with the ramifications of the decision. Lord Hope felt that by removing the immunity from suit in negligence, the approach of the majority contained seeds for challenging the whole concept of witness immunity. Lady Hale suggested that changing the law in this manner was “irresponsible” and best left to Parliament.

The position in Australia

The immunity of expert witnesses in Australia has been confirmed as recently as 2007 in the decision of Commonwealth v Griffiths. A key point of difference between Australia and the United Kingdom is the abolition of the corresponding immunity for advocates. The advocates’ immunity was abolished in the United Kingdom by the House of Lords decision of Hall v Simons, but continues to apply in Australia, having most recently been raised before the High Court in 2005 in D’Orta-Ekenaike v Victorian Legal Aid. This is an important difference because both the advocate and the expert witness have a paramount duty to the Court in common. To the extent that the advocates’ immunity continues to apply in Australia, then it is possible that expert witnesses will also remain immune from suit in negligence in so far as the immunity in both cases is underpinned by a common, but critical, public policy rationale.  

Likely impacts on the availability of expert evidence

The judgment in Jones v Kaney highlights that experts, even without immunity, are well protected from suits in negligence. The Court cited the difficulty of proving an action in negligence and the availability of professional indemnity insurance as countering the assertion that experts would be left vulnerable. In addition, the Court emphasised that the immunity had never been a full immunity as expert witnesses were (and remain) liable for perjury and sanction by professional bodies for misconduct during proceedings. Nonetheless, it is likely that in the appropriate case the question of immunity from suit will come before an Australian Court in the future and as such, experts should ensure they have adequate professional indemnity insurance coverage and that their retainer provides appropriate protection.