In a landmark decision, the Supreme Court has found in Jones v. Kaney1 that (save for defamation cases) the immunity that expert witnesses have enjoyed from claims based on breach of duty in relation to their participation in court proceedings should be abolished.  


The facts arose from a road traffic accident in which the expert had initially expressed the view that Mr Jones was suffering from post traumatic stress disorder (“PTSD”), but then went on to sign a joint expert’s statement (prepared by the opposing expert) stating that PTSD had not been suffered. The simple reason for the change of heart was that the expert had felt pressured to agree to the joint statement, even though it did not reflect her views. Unfortunately, the Court would not permit Mr Jones to instruct a new expert and so he had to settle his claim arising from the accident for less than he otherwise would. Mr Jones therefore tried to sue the expert for negligence but his claim was struck out in the High Court due to the expert’s immunity. Given the importance of the issue, however, the judge gave permission for an appeal to be heard by the Supreme Court (thus leap frogging the Court of Appeal).  


In the lead judgment, Lord Philips considered the purpose, scope and effects of the immunity. It originally took the form of an absolute privilege against a claim for defamation and then negligence and extended to all who took part in legal proceedings: judges, counsel and witnesses alike (both of fact and experts). The primary reason identified was the “chilling effect” that the risk of claims arising out of the conduct of legal proceedings would have. Claimants would be reluctant to litigate and witnesses reluctant to testify or, at least, to do so freely and frankly. Expert witnesses, in particular, might be reluctant to act if the evidence given was contrary to the client’s interests, leading to a risk of being sued. The possibility of a multiplicity of actions, whereby the value or truth of witnesses’ evidence might be tried all over again, was also potentially undesirable.

Supreme Court decision

Lord Phillips considered that the onus lay with the expert to show why the immunity should continue. The suggestion that experts would be reluctant to provide their services if the immunity was abolished was not justified: anyone who provides professional services involving a duty of care will, in any event, have a risk of being sued and can take out insurance to cover that risk.  

Further, the suggestion that an expert needs immunity, in order to give full and frank evidence to the court, was also rejected. Experts have a duty to give their honest opinion, even if this is adverse to the case of the expert’s client. If an expert has initially given advice which later proves to have been overly optimistic, then his duty to the court is to concede that change of view. However, such a change of view should not, in Lord Phillips’ view, translate into experts fearing being sued: the change of mind, even though adverse to the client’s case, merely amounts to the performance of the expert’s duty to the court. Therefore, while an unsuccessful litigant might pursue a negligence claim, actually mounting a credible case would not be easy. Diligent experts were unlikely to be harassed by vexatious claims by their clients for breach of duty.  

Opening views

Out of the seven Supreme Court judges giving judgment, five were in favour of allowing the appeal and thus abolishing expert’s immunity and two favoured dismissing the appeal and keeping the immunity intact. The two dissenting voices pointed out that the rule granting immunity to witnesses was longstanding and the removal of immunity would run counter to the authorities over many years. Further, it was pointed out that the justifications advanced for removal of immunity in civil cases would not necessarily extend to experts in other jurisdictions, particularly in criminal or family/child care cases, where the instruction of experts would not necessarily be by the client himself.  


Overall, however, the majority favoured the abolition of expert’s immunity. It was perhaps Lord Brown who summed it up most succinctly: “….. the gains to be derived from denying [experts] immunity… substantially exceed whatever loss might be thought likely to result from this…… The most likely broad consequence of denying expert witnesses the immunity….. will be a sharpened awareness of the risks of pitching their initial views of the merits of their client’s case too high or too inflexibly lest these views come to expose and embarrass them at a later date”.  

I for one would welcome this as a healthy development.