Illegality and Lewis-Ranwell v G4S Health Services (UK) Ltd and Others [2024] EWCA Civ138: A new turn in the well-worn road?

18/02/2026

Lewis-Ranwell v G4S Health Services (UK) Ltd and Others [2024] EWCA Civ 138 is the most recent decision in a line of authorities relating to the illegality defence. In Gray v Thames Trains Ltd [2009] UKHL 33 and Henderson v Dorset Healthcare University NHS Foundation Trust [2020] UKSC 43, both Claimants who had committed manslaughter failed in their claims in tort for damages arising from the crime. Mr Lewis-Ranwell successfully persuaded the Court of Appeal that these two cases should be distinguished as he was acquitted of manslaughter by reason of insanity but his case now heads for the Supreme Court.

Ex Turpi Causa

 As Lord Sumption said in Les Laboratoires Servier v Apotex [2014] UKSC 55; [2015] AC 430 at paragraph 25:

‘The ex turpi causa principle is concerned with claims founded on acts which are contrary to the public law of the state and engage the public interest. The paradigm case is, as I have said, a criminal act. In addition, it is concerned with a limited category of acts which, while not necessarily criminal, can conveniently be described as “quasi-criminal” because they engage the public interest in the same way … this additional category of non-criminal acts giving rise to the defence includes cases of dishonesty or corruption, which have always been regarded as engaging the public interest even in the context of purely civil disputes…’

Patel v Mirza

The most recent, and perhaps most significant, case in the area is Patel v Mirza [2016] UKSC 42; [2017] AC 467. The brief facts are that the Claimant had transferred funds to the Defendant with a view to the Defendant using them for insider trading. The Defendant did not, in fact, do so. The Claimant sought the return of the funds under the principles of unjust enrichment and the Defendant argued that the claim was barred by illegality. The Supreme Court reasoned that there were two discernible policy reasons for the common law doctrine or illegality as a defence to a civil claim: the first is that a person should not be allowed to profit from his own wrongdoing and the second is that the law should be coherent and not self-defeating, condoning illegality by giving with the left hand what it takes with the right hand. The Court further stated that public interest test would require consideration of the underlying purpose of any prohibition that has been transgressed, along with any other relevant public policies that might be rendered less effective by denying the claim and also keeping in mind that any result ought to be a proportionate response to the illegality.

Gray v Thames Trains

Perhaps the most stark example of preserving coherence in the law and avoiding the law becoming self-defeating is offered by the cases concerning criminal acts. In Gray v Thames Trains Ltd [2009] UKHL 33; [2009] 1 WC 1339, Lord Hoffmann said, at paragraph 32, the following:

‘The particular rule for which the appellants contend may, as I said, be stated in a wider or a narrow form. The wider and simpler version is that which was applied by Flaux J: you cannot recover for damage which is the consequence of your own criminal act. In its narrower form, it is that you cannot recover for damage which is the consequence of a sentence imposed upon you for a criminal act. I make this distinction between the wider and narrower version of the rule because there is a particular justification for the narrower rule which does not necessarily apply to the wider version.’

The result in Gray was that the Claimant, who had committed manslaughter as a result of psychological problems caused by the negligence of a Defendant, was precluded from recovering compensation from that Defendant in respect of general damages and loss of earnings consequential upon the crime and the sentence imposed.

Henderson v Dorset Healthcare

This approach was endorsed by the Supreme Court in Henderson v Dorset Healthcare University NHS Foundation Trust [2020] UKSC 43; [2020] 3 WLR 1124, rejecting that Patel v Mirza had somehow cleared the slate of usual precedent in the area. Henderson was a case where a Claimant, suffering from schizophrenia, had killed her mother and been convicted of manslaughter (on the grounds of diminished responsibility) and detained by way of a hospital order. She claimed damages from the NHS Trust in relation to losses arising from her loss of liberty and also for her share of the inheritance. The Claimant argued that Gray could be distinguished from Henderson because in Gray the Claimant could be said to be criminally culpable, whereas in Henderson she was not as culpable.

The Supreme Court considered the relevance of the personal responsibility for the illegality and said as follows:

“83. Although there does not appear to have been any specific finding by the trial judge in Gray as to the degree of his responsibility, I am prepared to assume that he was regarded as bearing a significant degree of responsibility. The difficulty for the appellant, however, is that the degree of responsibility involved forms no part of the reasoning of the majority. The crucial consideration for the majority was the fact that the claimant had been found to be criminally responsible, not the degree of personal responsibility which that reflected.

84. At para 41 of his judgment Lord Hoffmann rejected the argument that the narrower rule does not apply in cases where the claimant’s conduct “had not been as blameworthy as all that”. At para 51 he explained that “the sentence of the court is plainly a consequence of the criminality for which the claimant was responsible “. In the same paragraph, he explained the wider rule as being justified on the grounds that a claimant should not be compensated “for the consequences of his own criminal conduct ” (emphasis added).

85. At para 69 Lord Rodger endorsed the narrow rule, explaining that “a civil court will not award damages to compensate a claimant for an injury or disadvantage which the criminal courts of the same jurisdiction have imposed on him by way of punishment for a criminal act for which he was responsible “. At para 85 he endorsed the wider rule on the basis that “a person is not entitled to be indemnified for the consequences of his criminal acts for which he has been found criminally responsible ” (emphasis added).

86. In my judgment Gray cannot be distinguished. It involved the same offence, the same sentence and the reasoning of the majority applies regardless of the degree of personal responsibility for the offending.”

Lewis-Ranwell

The Supreme Court has recently given permission for another appeal arising out of similar facts. In Lewis[1]Ranwell v G4S Health Services (UK) Ltd and Others [2024] EWCA Civ 138; [2024] KB 745 the Claimant had been held on remand and in the care of the Defendant. He was released on bail and whilst on bail killed three elderly men acting under a delusional belief. The Claimant sought to bring a claim against the Defendant for negligent care and releasing him when it was not safe to do so. The Claimant was tried for murder but was found not guilty by reason of insanity. He was detained pursuant to a hospital order and subject to restrictions.

The Claimant brought a claim for compensation against the Defendant, seeking, amongst other things, an indemnity against any claim as might be made against him by family members of those deceased. The Defendants sought to have the action struck out, relying on the defence of illegality. Garnham J. rejected the application and Court of Appeal, by a majority, upheld the first instance decision.

The Court of Appeal

The Court of Appeal rejected the Defendant’s submission that there was no distinction to be made between the cases of Gray and Henderson and the present case. The court held that the insanity finding is premised on the individual not being able to distinguish between right and wrong and as such not having responsibility for his actions. As such, it would not be incoherent to take a different approach to such a case. In relation to the public confidence principle, Underhill LJ acknowledged that it was a difficult decision but ultimately was of the view that ‘someone who was indeed insane should not be debarred from compensation for the consequences of their doing an unlawful act which they did not know was wrong and for which they therefore had no moral culpability’. Underhill LJ noted some anomalies that might arise from this finding but decided that those would have to be considered on their own facts in due course (if arising).

Andrews LJ, in a dissenting judgment, disagreed. Andrews LJ said that she thought that there wasn’t a sufficient distinction to be made between Gray and Henderson and the index case. She also noted that insanity would be no defence to a claim in tort and considered that there was indeed a degree of incoherence in making the Claimant liable in tort to

‘pay compensation to his victims or their estates, and, on the other, permitting him to avoid the consequences of such liability, by passing responsibility for his actions to someone else, on the basis that he would not have committed those intentional and tortious acts had it not been for the defendants’ negligence’. Andrews LJ preferred to determine the case on the basis that a person should not, generally, be permitted to rely on their own deliberate tortious act as a necessary ingredient in a claim against a third party. She decided that ‘all the public policy considerations identified by Lord Hamblen JSC in Henderson as supporting denial of the claim are equally present here’.

The Supreme Court, including Lord Hamblen JSC, gave permission to appeal. The appeal is yet to be heard.

Comment

The defence of illegality is wide and eludes a precise definition. This case deals with a specific aspect but is sure to draw wider guidance from the Supreme Court, especially in relation to the public policy aspects of the case and the defence more generally. The arguments are powerfully made on both sides and those with an interest in illegality as a defence are strongly encouraged to read the full judgment of the Court of Appeal because the analysis is incredibly clear (whether you agree with one side of the argument or the other).