Home / Insight / Appeal court finds that the trial judge was entitled to remain “agnostic” and unpersuaded by competing causation theories

Appeal court finds that the trial judge was entitled to remain “agnostic” and unpersuaded by competing causation theories


Nash v Volkswagen Financial Services (UK) Ltd  [2023] EWHC 2326 (KB) | 21 Sep 2023

At the very heart of this appeal was the question of factual causation where there are two competing causes and where there are serious shortcomings with both potential causes and no obvious other cause. The recent judgment provides a helpful reminder of the principles the court will apply, as well as highlighting the risks and uncertainties that litigants face where factual causation is in dispute.  


On 7 January 2020, the claimant bought an ex-demonstration SEAT Leon from Johnsons Car Ltd (the dealership). On 22 February 2020, the claimant returned to the dealership as he could hear a noise inside the vehicle which was confirmed by a member of staff at the dealership. The claimant was asked to return on 26 February 2020 when he would be provided with a courtesy car; however, on the evening of 24 February 2020, the vehicle caught fire while parked on the driveway. The vehicle was deemed to be a total loss.

The internal vehicle inspection report from Volkswagen and the report by the claimant’s insurers concluded that the cause of the fire could not be attributed to a mechanical defect. Merseyside Fire & Rescue Service (which had attended on the evening of the fire) produced a brief report, which stated that the source of ignition was a “vehicle-only electrical fault”, although this supposed cause was recorded for the purpose of statistics only.

Claimant’s position

It was the claimant’s case that the vehicle must have been inherently defective, and the defendant was liable for the losses. The claimant relied on expert evidence from an automotive engineer, Mr John Dabek, who inspected the vehicle and concluded that, on the basis that the vehicle was recently purchased, had not been abused and was parked correctly, it follows that the fire commenced within the vehicle as a result of some sort of defect.

Defendant’s position

Dr Stephen Tomsett prepared a desktop report for the defendant in which he concluded that the most likely explanation for the fire was the careless disposal of a cigarette by a passer-by, igniting debris in the corner of the driveway, which spread to the vehicle.

Neither expert identified a specific vehicle defect and, at the first instance trial in the County Court, the recorder concluded that, while the case law suggests that the court does not need to identify a specific fault, it does still require the court to find that it is more likely than not that the fire was caused by a fault, albeit unknown, in the vehicle and he was unable to do so on the evidence presented.

Appeal to the High Court

The claimant appealed the decision on three grounds:

Ground 1: The recorder erred in law by not choosing between the two competing theories before him and not asking himself whether the “defect” theory was so inherently improbable that it could not be accepted.

The Appeal Court was satisfied that the recorder was entitled to ask himself the single unitary question, namely whether the claimant had established on the balance of probabilities that it was more likely than not that the fire was caused by reason of the vehicle defect hypothesis, rather than selecting which of the competing explanations was more probable. The Appeal Court held that the recorder did enough in this case to justify the finding and gave sufficient reasons for doing so.

Ground 2: The recorder did not give sufficient reasons for dismissing the claimant’s expert evidence and, in particular, his conclusion as to the cause of the fire.

This was also rejected, on the basis that the recorder explained the reservations about the claimant’s expert evidence and that he had made negative comments about the claimant’s evidence and positive comments about the defendant’s evidence.

Ground 3: The recorder put undue weight on the possibility of there having been some further unexplored possible cause for the fire when neither expert suggested this was likely and it was not put to the claimant’s expert in cross-examination.

The Appeal Court held that the recorder reminded himself of the proper approach to causation including the possibility of an unknown explanation, but this was the extent of the emphasis. The recorder was entitled to remain “agnostic”, i.e. not persuaded by or committed to either of the competing theories.

The appeal was dismissed, and all three grounds rejected.


The issue of factual causation in fire claims can be particularly uncertain because very often there is little positive evidence remaining in the aftermath of a serious fire. Cases will often turn upon the question of which party’s forensic expert evidence the court prefers, as well as the inferences which can be drawn from the remaining physical evidence. Inevitably, any such analysis is highly fact sensitive. Nonetheless, this judgment provides a helpful reminder of the legal principles which the court will apply in cases where there are two competing causes and where there are serious shortcomings with both potential causes and no obvious other cause.  

It is, therefore, imperative before proceeding to litigation to assess carefully the risks associated with whether a claimant can prove their claim on the balance of probabilities, and litigants should not assume that the court will choose the most likely cause from options presented by experts.


For more information, please contact:

Ana Kennedy - Solicitor

Email: akennedy@keoghs.co.uk

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