Henderson v Dorset Healthcare University NHS Foundation Trust [2020] UKSC 43

Ex turpi causa The respondent admitted negligently failing to return the appellant to hospital on the basis of her manifest psychotic state, which led to her stabbing her mother to death. The Supreme Court held that the previous case of Gray v Thames Trains Ltd [2009] UKHL 33M could not be distinguished, and should not be departed from, and that therefore the claim was barred by the doctrine of ex turpi causa non oritur actio (illegality).

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[2020] WLR(D) 592B

Supreme Court

Henderson v Dorset Healthcare University NHS Foundation Trust

[2020] UKSC 43B

2020 May 11, 12; Oct 30

Lord Reed PSC, Lord Hodge DPSC, Lady Black, Lord Lloyd-Jones, Lady Arden, Lord Kitchin, Lord Hamblen JJSC

Public policy— Illegality— Civil claim— Mental health patient killing mother during psychotic episode— Patient pleading guilty to manslaughter on ground of diminished responsibility and detained under unlimited restriction order— NHS trust admitting negligent failure to readmit patient to hospital following deterioration of condition— Patient claiming damages against NHS trust for breach of duty— Whether claim barred on grounds of illegality— Whether defence engaged where claimant lacking any significant responsibility for illegal act

The claimant, who had a history of schizophrenia with paranoia, killed her mother by stabbing her during a psychotic episode. At the time of the killing she was under the care of a community mental health team managed and operated by the defendant NHS trust. She pleaded guilty to manslaughter on the ground of diminished responsibility and was made subject to a hospital order for her treatment, with unlimited restriction for the protection of the public, pursuant to sections 37 and 41 of the Mental Health Act 1983. The claimant brought a claim in negligence against the trust, contending that she would not have killed her mother if it had not been for the trust’s breaches of duty in failing to respond in an appropriate way to her mental illness. The heads of claim included (i) general damages for loss of liberty and loss of amenity consequent on her detention and (ii) special damages for the loss of her share in her mother’s estate as a result of the operation of the Forfeiture Act 1982. The trust admitted breach of duty but contended that since the damages claimed were the consequence of the sentence imposed on her by the criminal court and/or her criminal act of manslaughter, they were irrecoverable on illegality or public policy grounds. The judge dismissed the claim, holding that even though the claimant’s personal responsibility for the offence was low, the entirety of the claim was precluded on the ground of the illegality inherent in her conviction. The Court of Appeal dismissed the claimant’s appeal, applying the principles set out in previous House of Lords authority (“the Gray principles”). The claimant appealed on the grounds that that authority either could be distinguished, as having been concerned with claimants who had significant personal responsibility for their crimes, or should be overruled, as being incompatible with the “trio of considerations” approach to illegality adopted in a subsequent Supreme Court decision, under which, she claimed, an assessment of relevant competing public policy considerations and proportionality factors would favour allowing her claim.

On the appeal—

Held, appeal dismissed. (1) The “trio of considerations” identified by the Supreme Court, although concerning a claim in unjust enrichment, set out the proper approach to the common law illegality defence across civil law generally. Since that guidance was derived from pre-existing case law, earlier decisions on the illegality defence remained of precedential value unless it could be shown that they were not compatible with that approach. It followed that the Gray principles would be applicable to the claim unless the House of Lords decision which formulated them was either distinguishable or the principles it enunciated were incompatible with the trio of considerations approach so as to require it to be departed from (paras 74, 76–77).

Patel v Mirza [2017] AC 467B, SC(E) applied.

(2) The Gray principles provided that there could be no recovery of damages which were the result of a sentence imposed for a criminal offence or which resulted from the intentional criminal act for which the defendant had been held responsible, because the inconsistency of allowing a claimant to be compensated for the consequences of his own criminal conduct would undermine the integrity of the legal system and risk bringing the law into disrepute and diminishing respect for it, thereby undermining public confidence in the law. Since the House of Lords had formulated those principles by reference to the fact that the claimant had been found to be criminally responsible rather than the degree of personal responsibility which that reflected, the fact that the claimant bore no significant personal responsibility for her actions did not afford a basis for distinguishing that case. Nor was there any ground to depart from the House of Lords decision. The principles in that case had been formulated as a matter of public policy and were compatible with the Supreme Court’s trio of considerations approach. Accordingly, the Gray principles were a proper part of the trio of considerations exercise in a case to which they were relevant (paras 36, 58, 83–86, 90–94, 96, 104–106).

Gray v Thames Trains Ltd [2009] AC 1399Not on Bailii!, HL(E) followed.

(3) In the instant case, the policy reasons which supported denial of the claim included not only the need to avoid inconsistency between the criminal and civil law and the effect that would have on public confidence, but also the gravity of the criminal offence, the public interest in the proper allocation of NHS resources, the very close connection between the claim and the offence, and the public interest in deterring, protecting the public from, and condemning unlawful killing. There were no countervailing policies sufficient to outweigh those considerations. Denial of the claim would not be disproportionate given the seriousness of the offence, which was the effective cause of the loss claimed. In relation to the loss of the claimant’s share in her mother’s estate, it would be inappropriate for the court to subvert the operation of the Forfeiture Act 1982 by permitting the claimant to recover from the defendant what she was not permitted to recover under that Act. Accordingly, all the heads of loss claimed in relation to the killing were irrecoverable (paras 125–131, 137–143, 149).

Nicholas Bowen QC, Katie Scott and Duncan Fairgrieve (instructed by Russell-Cooke llp, Putney) for the claimant.

Angus Moon QC, Cecily White, Judith Ayling and James Goudkamp (instructed by DAC Beachcroft llp, Bristol) for the defendant.

Colin Beresford, Barrister

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