The Annual Heilbron Lecture - Professor Rachael Mulheron KC (Hon)
Paul Brett Lecture Theatre, Yoko Ono Lennon Centre, Liverpool, L7 3NY
Thursday 5th November 2026
Professor Rachael Mulheron KC (Hon) - Queen Mary, University of London.
‘The New Wilsher’ with Professor Rachael Mulheron KC (Hon)
In her Heilbron Lecture Professor Mulheron will argue that the ‘single agent’ causal theorem per McGhee/Fairchild, and the ‘multi-agent’ per Wilsher, has become foggy, obscure, and strained in application in the medical negligence context – indeed, the cases have become downright difficult to reconcile; and
That a ‘purer’ solution would be to allow for multi-agent causation, but with a diminution in damages, corresponding to the percentage of probability which the negligent agent represents, on expert evidence/court approval – the sort of ‘fractional damages’ which Hotson v East Berkshire ruled out, but which should perhaps be rethought in light of the ongoing difficulties with Wilsher.
Abstract:
In Paul v Royal Wolverhampton NHS Trust [2024] UKSC 1, the UK Supreme Court changed the direction of English law, and its treatment of negligently-inflicted psychiatric injury. The majority held that, where a secondary victim witnesses a negligently-caused medical crisis (or its aftermath) that envelops a patient, and then proceeds to develop a recognised psychiatric injury as a result, that scenario cannot, in principle, found a claim for damages by that secondary victim. Rather, what is required for secondary victim compensation is, not a ‘medical crisis’ arising from the misdiagnosis or mistreatment of the patient, but a ‘medical accident’. This was explained as ‘an unexpected and unintended event which caused injury (or a risk of injury) by violent external means’ to the patient concerned. Hence, the law now differentiates between ‘medical crises’ and ‘medical accidents’. As a result of the ruling, it seemed that secondary victim recovery was dealt a significant blow. However, the reality is that several avenues still exist by which the secondary victim can seek to establish a right to recover damages because of medical conduct vis-à-vis the patient. Moreover, the ambit of the so-called ‘medical accident’ is now being tested in post-Paul case law. In this lecture, the strands of secondary victim recovery will be drawn together – and with a twist in the tail: what if the patient receives ‘medical advice’ from a chatbot which leads to the patient’s suicide?
Rachael Mulheron KC (Hon) FBA is Professor of Tort Law and Civil Justice at the School of Law, Queen Mary University of London. Her principal fields of academic research and publication concern Torts, Medical Negligence, Class Actions, and Civil Justice. Rachael was a member of the Civil Justice Council for almost a decade, chairing and authoring civil procedural topics and reports; and is a sitting member of the Competition Appeal Tribunal. Her work in the field of Tort law and Civil Justice has been cited with approval by the UK Supreme Court, as well as by the highest appellate courts in Canada, Australia and New Zealand. She has served, at the appointment of either government or judiciary, in numerous law reform roles, from ‘hot-tubbing’ in medical negligence cases, to the Disclosure Pilot in the Business and Property Courts, to the use of BTE insurance. Prior to her academic career, Rachael practised as a solicitor in Brisbane, Australia, first in general litigation and then in Construction Law. In 2021, Rachael was appointed as Honorary Queen’s Counsel for services to law reform.
‘The New Wilsher’ with Professor Rachael Mulheron KC (Hon)
In her Heilbron Lecture Professor Mulheron will argue that the ‘single agent’ causal theorem per McGhee/Fairchild, and the ‘multi-agent’ per Wilsher, has become foggy, obscure, and strained in application in the medical negligence context – indeed, the cases have become downright difficult to reconcile; and
That a ‘purer’ solution would be to allow for multi-agent causation, but with a diminution in damages, corresponding to the percentage of probability which the negligent agent represents, on expert evidence/court approval – the sort of ‘fractional damages’ which Hotson v East Berkshire ruled out, but which should perhaps be rethought in light of the ongoing difficulties with Wilsher.
Abstract:
In Paul v Royal Wolverhampton NHS Trust [2024] UKSC 1, the UK Supreme Court changed the direction of English law, and its treatment of negligently-inflicted psychiatric injury. The majority held that, where a secondary victim witnesses a negligently-caused medical crisis (or its aftermath) that envelops a patient, and then proceeds to develop a recognised psychiatric injury as a result, that scenario cannot, in principle, found a claim for damages by that secondary victim. Rather, what is required for secondary victim compensation is, not a ‘medical crisis’ arising from the misdiagnosis or mistreatment of the patient, but a ‘medical accident’. This was explained as ‘an unexpected and unintended event which caused injury (or a risk of injury) by violent external means’ to the patient concerned. Hence, the law now differentiates between ‘medical crises’ and ‘medical accidents’. As a result of the ruling, it seemed that secondary victim recovery was dealt a significant blow. However, the reality is that several avenues still exist by which the secondary victim can seek to establish a right to recover damages because of medical conduct vis-à-vis the patient. Moreover, the ambit of the so-called ‘medical accident’ is now being tested in post-Paul case law. In this lecture, the strands of secondary victim recovery will be drawn together – and with a twist in the tail: what if the patient receives ‘medical advice’ from a chatbot which leads to the patient’s suicide?
Rachael Mulheron KC (Hon) FBA is Professor of Tort Law and Civil Justice at the School of Law, Queen Mary University of London. Her principal fields of academic research and publication concern Torts, Medical Negligence, Class Actions, and Civil Justice. Rachael was a member of the Civil Justice Council for almost a decade, chairing and authoring civil procedural topics and reports; and is a sitting member of the Competition Appeal Tribunal. Her work in the field of Tort law and Civil Justice has been cited with approval by the UK Supreme Court, as well as by the highest appellate courts in Canada, Australia and New Zealand. She has served, at the appointment of either government or judiciary, in numerous law reform roles, from ‘hot-tubbing’ in medical negligence cases, to the Disclosure Pilot in the Business and Property Courts, to the use of BTE insurance. Prior to her academic career, Rachael practised as a solicitor in Brisbane, Australia, first in general litigation and then in Construction Law. In 2021, Rachael was appointed as Honorary Queen’s Counsel for services to law reform.
