The highest court will once again consider the basis and application of the doctrine that no recovery should flow from illegal acts (often cited in Latin as the ex turpi causa rule), something which has been before the Supreme Court on several occasions in recent years in very different factual settings. The latest case involves a claim by a psychiatric patient against an NHS Trust for losses arising from the death of her mother. She had killed her mother while under the Trust’s care and it was agreed this would not have happened but for failings in the care provided to her. Seven Justices will hear the case by video conference in mid-May.
The claimant was initially charged with her mother’s murder but the Crown subsequently accepted a plea of manslaughter by reason of diminished responsibility and she was sentenced to detention in psychiatric hospital. She began civil proceedings against the Trust which included claims for sums forfeited under her mother’s will, for losses arising out of her detention and for damages for PTSD consequent on her killing her mother.
The relevant common law was set out in two similar cases. In Clunis v Camden [CA, 1998] the claimant had killed after failings in the treatment of his schizophrenia. His damages claim for loss of liberty was rejected because of the ex turpi bar on recovery following his wrongful act. In Gray v Thames Trains [HL, 2009] the claimant sustained serious PTSD in the 1999 Ladbroke Grove train crash which lead him to kill in a road rage incident. His claim was also barred on the ex turpi basis.
However since those decisions the Supreme Court in Patel v Mirza  had re-examined the illegality rule further and refined its basis and scope. That nine, rather than the usual five, Justices heard Patel gives an indication of its weight.
The essence of the lead judgment in Patel, given by Lord Toulson, was that the illegality rule means it is against public policy to allow a claim if to do so would harm the integrity and coherence of the legal system. Furthermore, the issue should be approached by examining the purpose of the bar on recovery, any other public policy points which would be raised by refusing the claim, and by asking whether doing so would be a proportionate response to the wrongful act on which the claim is grounded. [He also set out a range of factors for evaluating this last aspect.]
In the Henderson case, the High Court and the Court of Appeal both held that Clunis and Gray had not been overruled by Patel and therefore the claim should be barred. It is this which the claimant is challenging in the Supreme Court.
Standing back from the detail, it is very clear that questions of the illegality defence and the ex turpi rule continue to raise difficult questions of application, scope and consistency. The underlying tension is between a rules-based approach and a more flexible analysis based on evolving ideas of public policy and proportionality.
There had been some hope that the decision in Patel might bring that to an end. What instead happened was that the nine-strong bench, although unanimous about the outcome in the claim, split on the reasoning by which it should be reached, thereby further emphasising the differences between the two possible approaches.
Lord Toulson in Patel drew from social justice concepts first articulated by Lord Mansfield in the late 18th century and preferred the more flexible approach, something in which he was supported by four other Supreme Court Justices. The others, however, were equally clear that Lord Toulson’s factors-based approach would not offer the necessary legal certainty and coherence that a clear-cut principle would. The tension was set out plainly by Lord Kerr:
“The way is now open for this court to make its choice between, on the one hand, cleaving to the rule-based approach … and, on the other, a more flexible approach, taking into account the policy considerations that are said to favour recognising the defence of illegality, those which militate against such recognition and the proportionality of allowing the defence to prevail.”
The court in Henderson will be led by its new President, Lord Reed, and it is notable that none of the seven Justices listed to hear the case was involved in Patel only four years ago.
Earlier this month in the Morrisons case Lord Reed had very carefully shifted the emphasis of the test for vicarious liability back towards a rules-based approach and away from the more flexible language employed by Lord Toulson in Mohamud in 2016. As in Patel, Lord Toulson had based his analysis in Mohamud on social justice concepts he traced back to the 18th century.
It remains to be seen which of the options on illegality identified by Lord Kerr that the newly constituted Supreme Court might prefer in resolving Henderson. Lord Reed’s recent decision in Morrisons to clarify an earlier decision of Lord Toulson in a very different legal area is merely an interesting coincidence and does not suggest in any way that it might favour a rules-based approach here.
Written by Alistair Kinley, director of policy and government affairs at BLM