The Supreme Court ruled on 30 March 2011 that (save in respect of defamation) it is time to bring to an end the immunity from suit traditionally extended to expert witnesses. So from now on if an expert witness is negligent in giving evidence in a trial it will be open to a person who has suffered as a result to sue the expert witness.

Although the case did not concern an employment matter, the ruling is, of course, of general application to all areas of litigation, including employment law.

In the case, a Mr Wynne Jones had been involved in a car accident. A clinical psychologist, Ms Kaney, diagnosed PTSD (post traumatic stress disorder). Proceedings were issued, liability was agreed, and the only question remaining was the level of damages. A consultant psychiatrist then examined Mr Jones and concluded that he was exaggerating his symptoms. On the order of the Court, the two experts produced a joint report, in which Ms Kaney now indicated that Mr Jones had misled her, and that he did not in fact suffer PTSD.

This, of course, damaged Mr Jones’ claim and he had to settle for less than he had anticipated.

Mr Jones sued Ms Kaney for negligence. She sought a strike out which the High Court granted, holding that in accordance with established case law it was bound to rule that, as an expert witness, she had immunity from such a claim in connection with preparing a joint statement for trial purposes.

Mr Jones appealed directly to the Supreme Court. He won by a 5-2 majority.

The Supreme Court concluded that the original rationale behind the immunity – concern that, in breach of his duty to the court, an expert witness might be reluctant to give evidence contrary to his client’s interest through fear of being sued – no longer applied. There was no conflict between the duty that the expert had to provide services to his client with reasonable skill and care and the duty he owed to the court. The same immunity used to apply, for similar reasons, to advocates and its removal in 2001 had not diminished the readiness of advocates to perform their duty. No evidence suggested that the immunity was necessary to secure an “adequate supply of expert witnesses”. It was time to remove it.

Any readers of this note intending to use the services of expert witnesses in a court or tribunal should take note of this new ruling (the case is Jones v Kaney [2011] UKSC 13, Supreme Court on 30 March 2011).