Publication: The e-Regulator

In Jones v Kaney, the Supreme Court had to determine whether public policy permits the retention of the immunity enjoyed by expert witnesses in claims by their own client for breach of a duty of care, contractual or tortious. Overruling the decision in Stanton v Callaghan [2000] QB 75, a majority of 5-2 (Lord Hope and Lady Hale dissenting) held it did not. Less than one month later, in the case of Baxendale-Walker v Middleton, the honourable Mr Justice Supperstone, sitting in the Queen’s Bench Division, upheld the immunity of expert witnesses as a defence to tortuous claims. This apparent contradiction is not however an example of a judgment decided per incuriam. Rather, it is a judgment illustrating the fine line drawn by the Supreme Court in Jones v Kaney.

Jones v Kaney

The respondent was a consultant clinical psychologist who had been instructed by the appellant’s solicitors to draft a report for litigation purposes on the Post Traumatic Stress suffered by the appellant as a consequence of him being injured in a road traffic accident. The respondent later signed a joint statement, drafted by the other side’s expert, that was deemed to be inaccurate and thus the respondent was alleged to have acted negligently. The question that arose was whether the appellant could bring a claim in negligence against the respondent in light of the immunity referred to above.

The ‘chilling factor’ explored by their Lordships is that the potential liability of expert witnesses could make them reluctant to carry out work for their client or that the expert may be reluctant to disclose evidence that proved adverse to their client’s case. This could ultimately undermine the justice system as a whole. The majority held that this argument did not warrant retaining the immunity for expert witnesses for several reasons.

Lord Phillips and Lord Dyson both referred to the existence of professional indemnity insurance for expert witnesses; the notion that such witnesses would be left vulnerable without this protection was ill founded. Further reference was made to provision 35.3 of the Civil Procedure Rules, assuring experts that their duty to the court effectively overrides their duty to the client.

The reasoning behind the removal of the advocate’s immunity acted as a template for the majority in Jones v Kaney. On this basis, it was held that few expert witnesses would succumb to the pressure of liability and provide inaccurate or incomplete evidence in support of their client’s case.

Finally, Lord Collins highlighted the existence of professional disciplinary bodies which are capable of granting sanctions against those expert witnesses who have acted unprofessionally in the giving or preparation of their evidence, sanctions which are capable of severely impacting on the livelihood of experts. The fact this risk exists has not prevented expert witnesses from providing evidence thus far.

Dissenting judgement

Lord Hope highlighted the fact that not all expert witnesses will be insured against claims for negligence, such as those who give expert evidence on one off occasions. In addition, he argued that Lord Phillips’ view that performance of the witness’ duty to the court will not result in his liability for breach of duty to his client “contradicts the justification for the immunity that is extended to witnesses generally, which is that there are grounds from time to time for believing that the fear of suit exists.”

The comparison between the advocate and expert witness is also dismissed with Lord Hope highlighting the fact that the advocate’s “principal duty” is owed to his client rather than the court; for the expert witness, the reverse is true.

The primary reason for both Lord Hope and Lady Hale refusing to overrule the immunity in question seems to lie in where to draw the line. For example, if the immunity were to be lifted in this context, what is the justification for retaining the immunity enjoyed by expert witnesses in all kinds of civil proceedings?  Both Lady Hale and Lord Hope highlight the uncertainty that surrounds the impact of removing the immunity and felt it “irresponsible to make such a change on an experimental basis”, choosing instead to leave the issue for Parliament, as advised by the Law Commission.

Baxendale-Walker v Middleton

Within this later case, the court had to determine whether to strike out particulars of claim made against various defendants involved in the regulatory and disciplinary proceedings against the claimant, a former solicitor who specialised in tax law and who was ultimately struck off. The claims included, inter alia, the torts of conspiracy to injure, conspiracy to defraud and malicious falsehood.

The Honourable Mr Justice Supperstone found in favour of the defendants, one of the grounds being that the 4th and 6th defendants (partners of a 7th defendant accountancy firm) were protected by witness immunity for a report they drafted, for litigation purposes, on the legality of the claimant’s tax avoidance schemes.

The 4th and 6th defendants appear to fall under the category of ‘expert’ owing to their services being called upon to produce a report on a specialised topic. Therefore, why were they able to rely upon the witness immunity denied to the respondent in Jones v Kaney? The simple answer, as accepted by Mr Justice Supperstone, lies in the Supreme Court’s judgment applying to claims made by clients against their own expert in negligence and leaving unaltered the law applicable to experts sued on similar grounds by the opposing party.

Accordingly, Jones v Kaney was distinguished and the defendants in Baxendale-Walker v Middleton succeeded in their defence.


The majority decision in Jones v Kaney may result in a ‘sharpened awareness’ of the risks surrounding inaccurate expert evidence with an inhibiting effect on the provision of services by such witnesses. Only subsequent litigation will determine whether the assumption that it will not, will hold true. With regard to Baxendale-Walker v Middleton, the fine line drawn by Jones v Kaney has materialised: Experts retain their immunity against an opposing party but not their instructing client. Now that inroads have been made into the removal of expert witness immunity the question that emerges is whether future judgments will contribute to this erosion and, if so, whether the immunity retained by alternate witnesses remains justified?