Diamond v Royal Devon & Exeter NHS Foundation Trust

Informed-consent causation remains conventional: a claimant must show that adequate disclosure would have changed the treatment decision. The counterfactual is assessed by reference to the actual patient, including personal circumstances, alongside objective clinical evidence. The court must not substitute a freestanding test of objective rationality. The exceptional Chester approach does not create damages for non-disclosure alone. It modifies causation only in unusual cases, ordinarily requiring proof that the operation would have been deferred. Psychiatric injury caused by later independent advice will fail without a pleaded and evidential causal link.

The appellant established at trial that informed consent had not been obtained before mesh repair of her abdominal hernia. The trial judge nevertheless found that, if properly advised about pregnancy-related risks and the alternative of sutured repair, she would still have chosen mesh repair. The judge rejected additional claims for psychiatric injury and for damages based solely on the invasion of autonomy. The appeal challenged the assessment of the appellant’s counterfactual choice, the rejection of psychiatric injury, and reliance on the exceptional causation reasoning associated with Chester v Afshar. The central issue was whether the trial judge had applied the wrong legal approach or reached findings unsupported by the evidence.

Appeal dismissed. Lady Justice Nicola Davies gave the judgment, with Lord Justice Floyd and Lord Justice McCombe agreeing.

1. The conventional but-for test applies to informed-consent claims. The patient must establish that, if warned of the material risks and alternatives, the patient would not have consented to the treatment. Under Montgomery v Lanarkshire Health Board [2015] 2 WLR 162, materiality is assessed by reference to a reasonable person in the patient’s position and to risks or alternatives which the doctor knows, or should know, the particular patient would regard as significant.
2. The trial judge applied that approach. He considered the appellant’s personal and social circumstances, the clinical evidence, and the distinction between accurately recalling events and reconstructing a hypothetical response with hindsight. His use of the word rationality did not impose a freestanding objective-rationality test. The finding that she would still have chosen mesh repair was properly open on the evidence and disclosed no material error of law or factual basis for appellate interference.
3. The psychiatric-injury ground failed. The case as tried was that distress followed advice given by another surgeon nearly three years later. That advice was not a foreseeable consequence of the original breach, was too remote, and lacked a pleaded and evidential causal foundation. Shock alone does not sound in damages.
4. There is no freestanding claim for damages merely because information was withheld or autonomy was infringed. Chester v Afshar [2005] 1 AC 134, as analysed in Correia v University Hospital of North Staffordshire NHS Trust [2017] EWCA Civ 356 and Duce v Worcestershire Acute Hospitals NHS Trust [2018] EWCA Civ 1307, does not remove the need for a causal connection. Its exceptional modification of ordinary causation requires a pleaded and evidenced case that the operation would have been deferred. That premise was absent here.

1. Court of Appeal (Civil Division) dismissed the appeal: [2019] EWCA Civ 585.
2. Queen’s Bench Division, HHJ Freedman sitting as a High Court Judge, found breach of the informed-consent duty but held that the appellant would still have chosen mesh repair and rejected the additional claims: [2017] EWHC 1495 (QB).