3 March 2022

Is Expert Witness Immunity in England and Wales Bulletproof?

BY: Andrew Merrilees | IN: Press


In this article Andrew Merrilees – Expert Witness, Chartered Quantity Surveyor and Director at CCi, reviews expert witness immunity in England and Wales, questioning is it bulletproof?

Andrew, reviews the precedents for the threshold for cases of professional negligence against an expert witness and the difficulties of suing an expert for professional negligence, highlighting the responsibilities of an expert witness and their overriding duty of independent and unbiased assistance to the court.

CCi has significant experience and is often called upon to supply experienced Expert Witnesses – independent and impartial experts who are trained in providing oral testimony in Court and for tribunals. With a global network of delay, quantum, and technical experts, and a high level of expertise and direct industry experience, these experts deliver forensic analysis and opinions and provide them in clear and concise expert reports.

Review of Judgements

On 26 January 2022, the High Court of England, and Wales decision in Radia v Marks [2022] EWHC 145 (QB)[1] kindled recollection of the Supreme Court case of Jones v Kaney [2011] UKSC 13.

In Jones v Kaney [2011] UKSC 13 it was decided that expert witnesses were not immune from claims in tort and contract, and which concerned the preparation of a joint statement by experts.[2]

However, in the recent case of Radia v Marks [2022] EWHC 145 (QB), the High Court dismissed a breach of duty claim in tort and contract against a medical expert who had given evidence as a joint expert in former employment tribunal proceedings.

Radia v Marks [2022] EWHC 145 (QB)

The Findings

The Claimant alleged that the Defendant’s medical expert Professor Marks misreported his chemotherapy weight loss by neglecting to undertake a proper review of his medical records.

The Claimant also alleged that had the expert undertook a competent assessment, the employment tribunal would have found in his favour.

Mrs. Justice Lambert set aside the claim in negligence against Professor Marks as it was found there was no duty of care owed for the claims made, there was no breach of duty, and causation was not proven.

The claim was set aside on several grounds which are briefly outlined below with reference to pertinent citations contained in the High Court decision (with my emphasis in bold).

Scope of Duty

“[58.] It had been, observed Lord Dyson, “rightly acknowledged” by Lord Chadwick in Stanton v Callaghan [2000] QB 75 at 88E that an expert was a professional man who undertook for reward to provide advice within his expertise. In Jones Lord Dyson found there to be no conflict between the duty owed by an expert to his client and his overriding duty to the court in CPR 35(3). He said at [99]: “His duty to the client is to perform his function as an expert with the reasonable skill and care of an expert drawn from the relevant discipline. This includes a duty to perform the overriding duty of assisting the court. Thus, the discharge of his duty to the court cannot be a breach of duty to the client.”

“[59.] The question for me therefore is not whether the defendant owed the claimant a duty of care but whether the harm or loss claimed falls within the scope of that duty. Causation does not answer that question: it does not follow that every element of loss which would have been avoided but for the breach of duty would have is actionable. See Lord Oliver in Caparo Industries plc v Dickman [1990] 2 AC 605 at 651: “the duty of care is inseparable from the damage which the plaintiff claims to have suffered from its breach: it is not a duty to take care in the abstract but a duty to avoid causing to the particular plaintiff damage of the particular kind which he has in fact sustained”. In determining whether the loss is of a kind for which the defendant must take care to protect the claimant, the court should consider the purposes for which the information was given and the circumstances in which it was given, see Lord Roskill in Caparo at 629B. It is necessary to see what risk the duty is supposed to guard against and whether the loss represents the eventuation of that risk. This must be judged objectively.”

“[61iii] The critical duties and responsibilities of an expert, consistent with the overriding objective, include objectivity and independence: expert evidence should be and should be seen to be the independent product of the expert uninfluenced by the exigencies of litigation; an expert witness should provide independent assistance to the court by way of objective unbiased opinion in relation to matters within their expertise (see “The Ikarian Reefer” [1993] 2 Lloyds Rep 68).  To extend the scope of the expert’s duty to the protection of a party from the risk of an adverse credibility finding would create a real conflict between the expert’s overriding duty to the court and his or her duty to the party. Lord Dyson in Jones aligned the duties on the basis that by complying with the overriding objective of independence and objectivity, the expert was fulfilling his duty to the client. But such an alignment would be unsustainable if the scope of the duty to the client was extended in the way proposed by the claimant in this case. All the more so, when, as here the expert is instructed jointly by both parties.”

Breach of Duty

“[68] Setting aside the difficulty of determining how the expertise of such a person could be judged (whether by the number of reports written, whether the person was a member of the Academy of Experts or had taken a course in expert reporting) these generic issues are ones for the judge to evaluate taking into account CPR 35[3]. The expert evidence has provided me with only marginal assistance in resolving this case.”


“[83] This claim fails for the reasons set out above. It fails both in tort and in contract. I note that the defendant also invites me to consider the duty nexus question and the legal responsibility question in the Khan six-point plan[4]. The duty nexus question adds nothing to my analysis in this case nor on its facts do the further obstacles raised by Ms. Whittaker[5] of remoteness of damage and the defense of illegality.”


Is expert witness immunity in England and Wales bulletproof?

The judgement in Radia v Marks set a precedent for the threshold for cases of professional negligence against an expert witness.  The decision highlights the complications of suing an expert for professional negligence.

The main legal issue was whether the loss was within the scope of the duty of care, and whether the scope of the Defendant’s duty to the Claimant extended to the protection from the risk of an adverse credibility finding.  Justice Lambert’s answer to that question is that it did not.[1]

Regarding the role of the expert witnesses, the decision served to underpin the responsibilities of an expert witness and their overriding duty of independent assistance to the court.

Selecting the ‘right’ Expert Witness is critical to a successful outcome. At CCi we have internationally respected independent expert witnesses with direct industry experience of all stages of the construction process. Armed with vocational knowledge we understand the composition and potential strengths for claims accompanied with credible expert opinion.

[1] https://www.bailii.org/cgi-bin/format.cgi?doc=/ew/cases/EWHC/QB/2022/145.html.

[2] https://en.wikipedia.org/wiki/Jones_v_Kaney.

[3] Part 35 of the English Civil Procedure Rules:- https://www.justice.gov.uk/courts/procedurerules/civil/rules/part35.

[4] Further reading on the scope of a duty care owed by expert witnesses to litigants is contained in the appeal case Khan v Meadows [2021] UKSC 21:- https://www.bailii.org/uk/cases/UKSC/2021/21.html.

[5] Counsel for the Defendant.

[6] Paragraph [60] Radia v Marks [2022] EWHC 145 (QB).