Misa Zgonec-Rozej & Ors v Dr Stephen Pereira

The material contribution doctrine is an exception to the but for test. It arises only where the evidence cannot establish, on the balance of probabilities, whether the injury would have occurred without the breach, but can show that the breach made more than a negligible contribution. Where factual causation can be determined on a but for basis, the doctrine has no role. On appeal, a factual causation conclusion will stand unless plainly wrong. A negligent handover does not establish causation without evidence linking it to the receiving clinician’s treatment and the loss.

The claimants, as dependants and estate representatives of John Jones QC, brought a negligence claim against Dr Stephen Pereira, a consultant psychiatrist, after Jones died while a voluntary inpatient. Claims against the hospital and Dr Bakshi, the treating consultant during part of the admission, were settled without admission of liability. Bourne J found three breaches by Dr Pereira but dismissed the claim because causation was not established. The claimants appealed on causation, material contribution and contributory negligence. The central issues were whether the inadequate handover and delayed psychotherapy caused the death, and whether material contribution could apply where factual causation was determinable on a but for basis.

The Court of Appeal unanimously dismissed grounds 1–3. Ground 4, concerning contributory negligence, did not require determination.

1. Handover and causation. The admission was urgent, and the trial judge had found that Dr Pereira had no real opportunity to formulate an inpatient treatment plan or make assumptions about Mr Jones’s participation in group therapy. A handover was not the same as a treatment plan. Although psychotherapy was reasonably inferable as having been mentioned, Dr Bakshi was the experienced consultant responsible for formulating the treatment plan after admission. In the absence of evidence about Dr Bakshi’s clinical decision-making and care, the judge could not determine whether any later omissions were attributable to the handover, to independent shortcomings, to lack of therapy or funding, or to care which was otherwise adequate. His conclusion that the handover caused no measurable harm was neither plainly wrong nor illogical. The standard was applied from McGraddie v McGraddie and Anor [2013] 1 WLR 2477.
2. Diagnosis and counterfactual reasoning. The finding that Dr Pereira’s bipolar diagnosis was defensible, and did not itself breach the duty of care, was unchallenged. The trial judge’s conditional observations at [224] were not strictly necessary and could not override the actual findings on diagnosis and breach. The later breach concerning prompt arrangement of individual therapy arose after the clinical position had materially changed following three weeks of inpatient care, and did not establish that the earlier handover caused the death.
3. Material contribution. Material contribution is a recognised exception to the but for principle. The Court of Appeal treated Bailey v Ministry of Defence [2009] 1 WLR 1052 as authoritatively summarising the doctrine and noted that it was followed in Williams v Bermuda Hospitals Board (NHSLA intervening) [2016] UKPC 4. The doctrine does not arise where factual causation can be determined on a but for basis in either party’s favour. The trial judge correctly found that such a determination was possible and separately assessed each breach. Ground 3 was therefore dismissed.
4. Contributory negligence. As the claim failed for lack of causation, the Court did not need to determine the proposed reduction under section 1(1) of the Law Reform (Contributory Negligence) Act 1945.

• Court of Appeal (Civil Division): In [2025] EWCA Civ 171, the appeal was dismissed on grounds 1–3. The Court did not determine ground 4.
• High Court of Justice, King’s Bench Division: Bourne J found three breaches of duty by Dr Pereira but dismissed the claim because none was proved to have caused Mr Jones’s death. The judge indicated that, if liability had been established, damages would have been reduced by 25% for contributory negligence.