Jones v Kaney

Factual and Procedural Background

The Appellant was injured in a road traffic collision on 14 March 2001. After liability was admitted, the dispute centred on quantum, particularly the psychiatric consequences of the accident. The Appellant’s solicitors instructed the Defendant, a consultant clinical psychologist, to act as an expert witness. In compliance with a court direction, the Defendant and the insurer’s psychiatrist produced a joint statement. The Defendant signed that statement, which effectively undermined the Appellant’s claim.

The Appellant asserted that the Defendant had been negligent in preparing and signing the joint statement without adequate scrutiny or amendment. Relying on Stanton v Callaghan, the Defendant obtained an order striking out the claim on the basis of expert-witness immunity. The first-instance judge granted a “leapfrog” certificate, allowing a direct appeal to the Supreme Court to determine whether such immunity should continue to shield an expert from liability in negligence.

Legal Issues Presented

1. Whether an expert witness enjoys immunity from a negligence suit brought by his or her own client in respect of preparing a joint witness statement (or other pre-trial work) for use in legal proceedings.
2. More broadly, whether public policy justifies retaining any civil immunity for expert witnesses in relation to the performance of their professional duties.

Arguments of the Parties

Appellant’s Arguments

• The rationale for witness immunity (fear of vexatious defamation claims) does not apply to contractual or tortious duties owed by paid experts to their clients.
• Expert witnesses are analogous to advocates, whose immunity was abolished in Arthur JS Hall & Co v Simons; accountability should likewise follow for experts.
• The so-called “chilling effect” is unproven; professional indemnity insurance and existing disciplinary mechanisms already manage legitimate risks.
• The immunity’s boundaries are uncertain (“fuzzy”), producing arbitrary results and paradoxes—particularly when experts must correct earlier opinions.

Defendant’s Arguments

• Immunity is rooted in centuries of authority designed to protect the administration of justice and remains necessary to ensure experts speak frankly, even if that disadvantages their clients.
• Removing immunity risks a shortage of willing experts and may pressure them to tailor evidence to avoid litigation, contrary to the CPR’s demand for independence.
• Existing exceptions (disciplinary proceedings, wasted-costs orders) are tightly linked to court control; extending liability to private actions would upset the settled balance.
• Line-drawing problems would create uncertainty across criminal, family and other public-law proceedings, potentially undermining access to justice.

Table of Precedents Cited

Court's Reasoning and Analysis

Majority (5 Judges)

• Witness immunity exists to prevent deterring honest testimony, not to shield professionals from accountability to paying clients.
• Expert witnesses voluntarily assume contractual and tortious duties; no principled basis for different treatment from other professionals.
• Purported “chilling effect” is speculative; insurance, reputation and disciplinary regimes already incentivise competence.
• Immunity’s boundary is inherently uncertain, creating paradoxes and unfairness (e.g., joint experts, pre-trial concessions).
• Comparable removal of advocate immunity has not harmed justice; analogy supports abolition here.
• Absolute privilege in defamation remains untouched; abolition is confined to negligence (or other civil wrongs) owed to the client.

Dissent (2 Judges)

• Long-standing precedent grants immunity to all witnesses; exceptions should be made by Parliament, not judicial innovation.
• Removing immunity risks tactical or vexatious litigation by disappointed parties, especially in sensitive areas (criminal, family).
• Difficult to craft clear limits; potential inconsistencies could disrupt expert participation and access to justice.
• Existing sanctions (discipline, wasted costs) already mitigate misconduct without eroding systemic protections.

Holding and Implications

APPEAL ALLOWED.

The Supreme Court abolished the civil immunity previously enjoyed by expert witnesses in respect of negligence (and analogous tort or contract claims) owed to their own clients for work connected to legal proceedings, including preparation of joint statements. Absolute privilege against defamation is unaffected.

Implications:

• Clients may sue expert witnesses for negligent preparation or opinions, aligning experts with other professionals.
• Experts must maintain professional indemnity cover and adhere strictly to their duties under CPR Part 35 (or equivalent rules).
• Courts remain able to sanction experts via wasted-costs orders or disciplinary referral; the decision adds a further layer of accountability.
• No new precedent was set regarding liability toward opposing parties or the court; focus is the expert–client relationship.