Lewis-Ranwell v G4S Health Services (UK) Ltd and others

Factual and Procedural Background

This Supreme Court judgment (heard July 2025; given January 2026) concerns a civil claim brought by the Claimant/Respondent against multiple defendants following a series of violent incidents in February 2019. The Claimant/Respondent, who had a prior diagnosis of schizophrenia and prior periods in psychiatric intensive care, was arrested twice in early February 2019 and detained in police custody. During those detentions, he behaved violently and appeared acutely unwell. He was seen or spoken to by mental health professionals associated with Company A (a private provider of forensic medical services in custody) and The NHS Trust (responsible for a liaison and diversion service). A face-to-face assessment discussed during the second detention did not occur, and a Mental Health Act assessment discussed with an approved mental health professional employed by The Council was not arranged.

Later on 10 February 2019, during a serious psychotic episode, the Claimant/Respondent killed three elderly men in their homes. After further events, he was compulsorily detained in The Hospital under the Mental Health Act and later charged with three counts of murder and two counts of wounding with intent. At trial in late 2019, the jury returned verdicts of not guilty of murder by reason of insanity. The court then made a hospital order with restrictions (Mental Health Act, sections 37 and 41) pursuant to the Criminal Procedure (Insanity) Act 1964, and the Claimant/Respondent remained detained in The Hospital.

In February 2020, the Claimant/Respondent issued civil proceedings against four defendants: Company A, The Police Authority, The NHS Trust, and The Council. He alleged negligence and also pleaded breaches of articles 3 and 8 of the European Convention on Human Rights. He sought damages across numerous heads, including psychiatric injury, loss of liberty, reputational harm, loss of earnings, future care/treatment costs, and an indemnity against civil claims by victims’ families. All defendants denied liability, pleaded illegality and contributory negligence, and The Council also denied owing a duty of care.

Company A, The NHS Trust, and The Council applied to strike out the negligence claim / obtain summary judgment on the basis that it was barred by illegality. Judge Garnham dismissed those applications. The Court of Appeal (majority) dismissed the appeal. The Supreme Court granted permission to appeal; a proposed issue about whether illegality barred the Human Rights Act 1998 claim was not pursued. The Supreme Court addressed whether the illegality defence barred the negligence heads of loss.

Legal Issues Presented

1. Whether the defence of illegality is engaged by the Claimant/Respondent’s civil claim in negligence, given that he was found not guilty of murder by reason of insanity.
2. If engaged, whether illegality bars the negligence claim in whole or in part.

Arguments of the Parties

Appellants’ Arguments

• The negligence claim should be struck out / summarily dismissed because the losses claimed flow from the Claimant/Respondent’s unlawful killings and from lawful detention ordered by the criminal court, engaging the illegality defence.
• Allowing recovery would create incoherence between criminal and civil law (including compensating detention ordered for public protection) and offend public confidence, including the propriety of using public funds to compensate the perpetrator of unlawful killings.
• The Claimant/Respondent’s indemnity head (seeking to be indemnified against claims by victims’ families) was objectionable as it would impermissibly shift responsibility for intentional torts; submissions were also made that such an indemnity would likely fail on duty, remoteness, and causation grounds.
• Concerns were raised about the potential procedural consequences of permitting such claims, including risks of inconsistent outcomes if defendants in civil proceedings sought to dispute the criminal verdict of insanity.

Claimant/Respondent’s Arguments

• Because the criminal verdict was not guilty by reason of insanity, there was no criminal responsibility; the illegality defence should not apply (or should not bar the claim), particularly where the Claimant/Respondent lacked moral culpability.
• Public policy favours adjudication of civil wrongs; allowing claims can expose failures in care and promote improvements in services.
• Denying relief would be inconsistent with the criminal verdict that the Claimant/Respondent should not be punished, and (on the Court of Appeal majority’s approach) would improperly treat an insanity case like diminished responsibility cases.

Table of Precedents Cited

Precedent	Rule or Principle Cited For	Application by the Court
Holman v Johnson (1775) 1 Cowp 341	Classic statement of illegality/ex turpi causa as a public policy doctrine.	Used as the historical starting point and to emphasise the public policy nature of the defence.
Tinsley v Milligan [1994] 1 AC 340	The “reliance test” and its later criticism.	Discussed as background; court proceeds on the post-Patel structured approach rather than reliance.
Al Hassan-Daniel v Revenue and Customs Comrs [2010] EWCA Civ 1443; [2011] QB 866	Illegality not argued as a bar to Human Rights Act claims in courts below.	Explained why illegality was not pursued against the Human Rights Act claim.
Gray v Thames Trains Ltd [2009] UKHL 33; [2009] AC 1339	Public policy bars recovery for losses consequent on a claimant’s unlawful killing and resulting sentence/detention; “narrower” and “wider” rules.	Applied by analogy; court held the Claimant/Respondent’s heads of negligence loss were barred under similar coherence/public confidence reasoning.
Hounga v Allen [2014] UKSC 47; [2014] 1 WLR 2889	Illegality grounded in public policy; balancing competing policies.	Used as part of development towards the structured approach.
Saunders v Edwards [1987] 1 WLR 1116	Connection/proportionality considerations in illegality.	Referenced in development of policy-based analysis.
Les Laboratoires Servier v Apotex Inc [2014] UKSC 55; [2015] AC 430	Competing approaches to illegality; “public interest” and “quasi-criminal” concepts.	Used in threshold discussion; court framed the threshold by reference to public interest and coherence.
Bilta (UK) Ltd v Nazir (No 2) [2015] UKSC 23; [2016] AC 1	Illegality debate and differing judicial approaches.	Used as part of doctrinal history.
Patel v Mirza [2016] UKSC 42; [2017] AC 467	Controlling structured approach: (a) purpose of prohibition, (b) other policies, (c) proportionality, centred on integrity/coherence of the legal system.	Applied as the analytical template; central to the decision to bar the negligence claim.
Henderson v Dorset Healthcare University NHS Foundation Trust [2020] UKSC 43; [2021] AC 563	Affirms Gray as consistent with Patel in unlawful killing/detention claims; rejects “no significant responsibility” distinction as decisive.	Used to support that coherence/integrity concerns can justify barring claims even where sentencing has no penal element; court rejected reading Henderson as implying insanity cases are exempt.
Grondona v Stoffel & Co [2020] UKSC 42; [2021] AC 540	Clarifies application of Patel; policy factors at a higher level; proportionality focuses on case detail.	Used to explain the method and intensity of the Patel analysis.
Hewison v Meridian Shipping Services PTE Ltd [2002] EWCA Civ 1821; [2003] ICR 766	Illegality may bar some heads of loss but not others.	Cited to note remedial flexibility (though the court concluded all heads failed here).
Ali v HSF Logistics Polska sp z oo [2024] EWCA Civ 1479; [2025] 4 WLR 8	Selective exclusion of heads of loss; “adaptive flexibility” of remedies.	Cited as a general principle on partial bars.
Khan v Hussain [2019] CSOH 11; 2019 SC 322	Scottish application of illegality reasoning by analogy to Gray.	Used as comparative domestic material supporting coherence-based illegality analysis.
DD v NHS Fife Health Board [2022] SAC (Civ) 27	Scottish approach: strike out losses flowing from claimant’s criminal convictions while allowing other losses to proceed.	Cited as an example of discerning application of illegality to heads of loss.
Clunis v Camden and Islington Health Authority [1998] QB 978	Earlier authority barring negligence claim where claimant convicted of manslaughter; includes obiter distinction about insanity.	Court agreed with the core outcome but rejected any suggestion that insanity would necessarily avoid illegality.
Askey v Golden Wine Co Ltd [1948] 2 All ER 35	Indemnity against criminal punishment is not recoverable.	Used in explaining the “narrower rule” logic in Gray.
British Columbia v Zastowny [2008] 1 SCR 27	Support for barring recovery for imprisonment consequences; coherence rationale.	Discussed within Gray and overseas authority context.
Rail Authority of New South Wales v Wiegold (1991) 25 NSWLR 500	Overseas support for barring recovery for consequences of criminal acts/sentence.	Cited as comparative authority referenced in Gray.
Hunter Area Health Service v Presland (2005) 63 NSWLR 22	Overseas approach to claims following homicide where claimant acquitted by reason of mental illness; public policy concerns.	Treated as closely analogous; court noted Commonwealth authority tending to support barring recovery.
Ellis v Counties Manukau District Health Board [2006] NZHC 826; [2007] 1 NZLR 196	New Zealand approach: strike out/deny duty in analogous circumstances.	Cited as supporting a restrictive approach, albeit framed as duty rather than illegality.
Barker v Barker 2022 ONCA 567	Ontario approach: illegality can apply to wrongful conduct even absent criminal responsibility.	Cited as supporting applicability of illegality in insanity-acquittal contexts.
Lingle v Berrien County 522 NW 2d 641 (Mich App 1994)	US example applying illegality notwithstanding insanity verdict.	Used as comparative material (limited persuasive weight).
Boruschewitz v Kirts 554 NE 2d 1112 (Ill App 1990)	US example rejecting illegality in a mental illness context.	Used as comparative material showing split approaches.
Bruscato v O'Brien 705 SE 2d 275 (Ga App 2010); 715 SE 2d 120 (2011)	US example declining to strike out; notes claims not wholly attributable to killing and absence of guilt findings.	Used as comparative material; not determinative.
Hall v Hebert [1993] 2 SCR 159	Coherence/integrity rationale: law should not “give with one hand what it takes with the other.”	Relied on to reinforce that coherence is the core rationale for illegality analysis.
Corr v IBC Vehicles Ltd [2008] UKHL 13; [2008] AC 884	Observation that criminal-law insanity line is “blunt” and not needed in civil tort.	Used to justify not letting criminal-law insanity/diminished responsibility categories determine civil illegality scope.
Weaver v Ward (1616) Hob 134	Insanity not a defence to trespass to the person/battery.	Used to show the claimant remains liable in tort notwithstanding insanity verdict, informing coherence concerns.
Morriss v Marsden [1952] 1 All ER 925	Reinforces that insanity does not preclude battery liability.	Used with Weaver to support the coherence analysis.
Dunnage v Randall [2015] EWCA Civ 673; [2016] QB 639	Objective negligence standard excludes consideration of a defendant’s insanity.	Used to show civil law does not track criminal responsibility; supports coherence-based illegality reasoning.
Palmer v Tees Health Authority [2000] PIQR P1	Limits on duties owed to third parties to prevent harm by others.	Used to illustrate that victims’ estates may not have claims against the defendants, intensifying perceived incoherence if the claimant can recover.
Robinson v Chief Constable of West Yorkshire Police [2018] UKSC 4; [2018] AC 736	Principles limiting negligence liability for omissions/failure to protect third parties.	Used alongside Palmer as part of the coherence/public confidence analysis.
Meah v McCreamer (No 2) [1986] 1 All ER 943	Remoteness concerns relevant to indemnity-like claims linked to criminal conduct.	Cited in defendants’ submissions as to why indemnity would be too remote.
Traylor v Kent and Medway NHS Social Care Partnership Trust [2022] 4 WLR 35	First-instance obiter suggesting illegality should not apply where M'Naghten is satisfied.	Not followed; Supreme Court treated it as non-binding and disagreed with the suggested limitation.
Loake v Director of Public Prosecutions [2017] EWHC 2855 (Admin); [2018] QB 998	Insanity under the “wrong” limb may leave mens rea intact though criminal responsibility is negatived.	Used to explain (on the assumed basis) why the claimant likely had mens rea but was not criminally responsible.
Felstead v The King [1914] AC 534	Special verdict historically treated as acquittal, not conviction.	Used to explain the legal character of insanity verdicts.
M'Naghten's case (1843) 10 Cl & Fin 200	Common-law test for insanity.	Used to explain criminal verdict context; court declined to make illegality hinge on limb distinctions.
R v Keal [2022] EWCA Crim 341; [2022] 4 WLR 41	Clarified “wrong” includes moral wrongness.	Noted to explain the criminal trial direction used in 2019 differed from later clarification.
Attorney-General's Reference (No 3 of 1998) [2000] QB 401	Requirement prosecution prove actus reus before special verdict; protections in insanity procedure.	Used to explain implications of the insanity verdict for what was established in the criminal process.
R v Antoine [2001] 1 AC 340	Role of jury and actus reus in insanity cases; burden regarding other defences.	Used to explain what the jury verdict necessarily entailed in procedural terms.
R v Birch (1989) 90 Cr App R 78	Effect of section 37/41 orders; hospital regime and public safety restrictions.	Used to explain the nature/purpose of detention (public protection, not punishment).
R v Calocane [2024] EWCA Crim 490; [2024] 4 All ER 1063	Difference between hospital/restriction orders and hybrid orders.	Used to contextualise the detention regime and its legal character.
R v Foye (Lee Robert) [2013] EWCA Crim 475; (2013) 177 JP 449	Burden of proof for diminished responsibility.	Used as part of the criminal-law background contrasting diminished responsibility and insanity.
R v Wilcocks [2016] EWCA Crim 2043; [2017] 4 WLR 39	Burden/proof issues for diminished responsibility.	Used for criminal-law background.
R v Dunbar [1958] 1 QB 1	Standard of proof (balance of probabilities) for diminished responsibility plea.	Used for criminal-law background.

Court's Reasoning and Analysis

Procedural posture: Because the appeal arose from strike-out / summary judgment applications, the court proceeded on assumed facts in the Claimant/Respondent’s pleaded case, noting many allegations were disputed.

1) Threshold: whether illegality is engaged

The court held that a threshold is needed so that trivial unlawfulness does not bar otherwise valid claims. It rejected the proposition that illegality is engaged only when conduct attracts criminal responsibility. Drawing from the public-policy rationale (integrity/coherence of the legal system), it held the Claimant/Respondent’s conduct—unlawful killings—engaged the public interest even though he was not criminally responsible by reason of insanity. The court disagreed with the Court of Appeal majority’s “bright-line” approach that would exclude insanity cases from illegality, reasoning that criminal-law categories should not “fetter” civil-law illegality analysis and that the key inquiry is coherence/integrity, not moral culpability alone.

The jury’s special verdict established that the Claimant/Respondent did the acts constituting the actus reus of murder. In the particular circumstances, the court considered the verdict did not negate mens rea (on the evidence summarised), but it treated that point as of limited significance and declined to hinge the threshold on which M'Naghten limb applied. The acts were neither justified nor treated as justified by insanity; the court characterised insanity as excusing criminal liability rather than justifying the killings. Because the hospital and restriction orders were required for public protection as a consequence of those actions, the conduct crossed the public-interest threshold and engaged the illegality defence.

2) The Patel structured assessment

Stage (a): purpose of the prohibition and whether denial enhances it. The prohibition transgressed was the fundamental injunction against unlawful killing, whose purposes include preservation of life, respect for the sanctity of life, deterrence, public condemnation, and acknowledgement of wrong to victims and their families. Although an insanity verdict removes criminal responsibility and shifts criminal disposal towards public protection rather than punishment, the court held the prohibition and its purposes apply “with equal force.” The court accepted deterrence may be limited in insanity cases but endorsed the view that a clear rule that “unlawful killing never pays” may have some broader deterrent effect.

The court then identified “a series of inconsistencies” that would arise if the negligence claim proceeded, undermining the integrity of the legal system:

• Compensating the Claimant/Respondent for loss of liberty during detention ordered by the criminal court for public protection would be inconsistent with the lawful detention regime itself (engaging the “narrower rule” described in Gray).
• The Claimant/Respondent remains liable in tort (battery) to victims’ estates/dependants despite insanity; allowing him to recover damages from the defendants for the consequences of his own intentional acts would be inconsistent with that continuing civil responsibility.
• The court noted that victims’ estates/dependants would be unlikely to succeed in claims against the defendants because the defendants were unlikely to owe them a duty to protect them from third-party violence; it considered that public perceptions of injustice could arise if the perpetrator could recover where victims could not.
• The indemnity head was particularly problematic: allowing an indemnity against claims by victims’ families would shift civil responsibility for the Claimant/Respondent’s intentional torts to others, bringing the law into disrepute and contradicting the public-policy rationale identified in Gray and Henderson.

The court also considered practical coherence risks concerning whether civil defendants could dispute the criminal insanity verdict (risking inconsistent outcomes) or be bound by it despite non-participation.

Stage (b): countervailing public policies. The court accepted a general public interest in courts adjudicating civil wrongs and acknowledged that civil litigation can expose substandard care and drive improvements. However, it noted alternative mechanisms (inquests and public inquiries) better suited to systemic learning, and it specifically recorded that an inquest into the deaths had been opened with a review hearing scheduled in July 2025 and with the coroner’s power to issue reports to prevent future deaths. It rejected the argument that denying the negligence claim would contradict the criminal verdict or amount to punishing the Claimant/Respondent; rather, denial was framed as necessary to prevent incoherence in the legal system. The court concluded stage (a) considerations “greatly outweigh” stage (b).

Stage (c): proportionality. Applying factors identified in Patel, the court held denial was proportionate: (i) the killings were of the utmost seriousness, (ii) the conduct was central and the effective cause of all claimed heads of loss, and (iii) even assuming the defendants’ negligence for strike-out purposes, the Claimant/Respondent’s acts remained unlawful killings. Denial was therefore not disproportionate.

Relationship with earlier case law. The court held its result was consistent with Gray and Henderson (and with the policy-based approach in Patel), and it rejected an obiter suggestion in Clunis that insanity might alter the outcome. It also considered the outcome aligned with the “preponderance” of Commonwealth authority, including Presland, Ellis, and Barker.

Holding and Implications

ALLOW APPEAL

The Supreme Court held that the illegality defence was engaged by the Claimant/Respondent’s unlawful killings despite the verdict of not guilty by reason of insanity, and that—following the Patel v Mirza structured analysis—the defence bars the negligence claim as pursued against the appellant defendants.

The direct effect is that the Claimant/Respondent cannot recover negligence damages for the claimed heads of loss (including losses flowing from detention and the claimed indemnity) from Company A, The NHS Trust, and The Council on the basis addressed in this judgment. The judgment emphasises coherence and public confidence as central to illegality analysis in this context. The opinion notes that proceedings under the Human Rights Act 1998 were not pursued as barred by illegality in the courts below and were expected to proceed to trial, and it also notes that The Police Authority had not applied to strike out the claim.