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

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.