The case of Leach is a helpful reappraisal of the law of material contribution to cases of PTSD in a clinical negligence context.
On 18th September 2016, the Claimant suffered a subarachnoid haemorrhage (SAH) as a result of a ruptured aneurysm. The Claimant recovered well from the haemorrhage, but she was left with significant Post-Traumatic Stress Disorder (PTSD) manifesting itself in significant anxiety. The ambulance took 109 minutes to reach the Claimant. Of that total time, the Defendant admitted a 31-minute period of negligent delay in the ambulance arriving at the Claimant’s house for the purpose of transporting her to hospital.
The central issue for determination therefore concerned causation and in particular, whether the negligent delay caused or materially contributed to the onset of the Claimant’s PTSD. Quantum was agreed in the sum of £40,000 subject to causation.
In his skeleton argument, the Defendant’s Counsel contended that the proper approach was to determine causation on the conventional ‘but for’ test. He relied upon the evidence of Dr Bowers, Consultant Psychiatrist, and asserted that the Claimant would have developed PTSD irrespective of any negligent delay. Conversely, Claimant’s counsel relied upon the evidence of Dr Smith and contended that it was not possible to decipher the specific temporal moment in which the PTSD was triggered. He relied upon the principles summarised in Bailey v Ministry of Defence [2009] 1 WLR 1052 and contended that the negligent period of delay made a material contribution to the onset of her PTSD.
HHJ Freedman found in favour of the Claimant. He found that whilst it was possible that she was destined to suffer from PTSD from the moment she suffered her SAH, to reach such a conclusion on the balance of probabilities was a step too far. He drew upon the reasoning of Globe J in Ceri Leigh v London Ambulance NHS Trust [2014] EWHC 286 who had emphasised the impossibility of predicting on any scientific or mathematical basis (whether prospectively or retrospectively) when a person exposed to trauma is likely to go on to suffer. HHJ Freedman found that the negligent delay was approximately one third of the overall period and it would be verging on the absurd to find that it had made no material contribution to the onset of her PTSD. He further found that as the condition was indivisible, there was no basis upon which the Court should undertake an apportionment exercise.
Eliot Woolf QC, a barrister in our clinical negligence team commented on the case as follows:
When it comes to considering causation of PTSD, this decision reaffirms that the Courts will have no difficulty in finding that it is an indivisible condition and accordingly open to the proper application of the Bailey test on material contribution. However, it should not be presumed that the Courts will necessarily conclude that all forms of psychiatric illness are indivisible and thereby incapable of apportionment.
On the one hand and very much in favour of Claimants are the observations of Smith LJ in Dickins v O2 [2008] EWCA Civ 1144, who doubted whether psychiatric harm could ever be divisible or dose-related, an issue which she revisited forcefully in her Munkman lecture ‘Causation – the Search for Principle’ published in JPIL in 2009. In Dickins, she was commenting, obiter, on the approach adopted by Hale LJ (as she was then) in Hatton v Sutherland [2002] EWCA Civ 76 where it was recognised that there may be cases where the harm would be divisible and capable of apportionment. This issue was revisited by the Court of Appeal in BAE Systems (Operations) Ltd v Konczak [2017] EWCA Civ 1188, where the Court concluded that if there were differences between the views expressed in Hatton and Dickins, Hatton should be followed, albeit recognising that it will always turn on the facts and the evidence.
As an aside, the recent decision of HHJ Auerbach in Davies v Frimley Health NHS Foundation Trust [2021] EWHC 169 provides a further very helpful summary of the case law in relation to material contribution in general (a case concerning delayed diagnosis and management of meningitis).
