Expert reports: the triumph of form over substance?

26 May 2022

It is easy to be lulled into a false sense of security that the formal requirements for an expert report, as set out in CPR 35.10, Practice Direction 35 and the Guidance for the Instruction of Experts in Civil Claims to which it refers (PD 35.1), matter far less than what an expert actually says.

True it is that many experts fail to summarise the range of opinion rather than just expressing their own (PD 35.3.2(6)) and this is often overlooked in the litigation. How often have you seen an expert set out the substance of all material oral instructions they had received, rather than a brief (if any) mention of the written instructions? CPR 35.10(3) requires them to do set out both but when was the last time someone objected that an expert had not?

The Guidance stresses the imperative that is transparency and that (a) the instructions to an expert should be listed, with dates, in the report or an appendix; and (b) “The omission from the statement of ‘off-the-record’ oral instructions is not permitted.” (at [55]). That is undoubtedly a requirement which is honoured more in the breach than the observance. Another similar point which is routinely overlooked by experts is the obligation when addressing questions of fact and opinion, to keep the two separate (Guidance at [57)]. Those are commonly woven together in reports in a way which is difficult to unpick for the instructing party, let alone the other side.

So, it is perhaps a wake-up call for us all to see a High Court case where failures of form in an expert report were central to the expert’s opinions being rejected by the Court: Pal v Dr Damen & Belgo International Research [2022] EWHC 004697 (QB). That was a clinical negligence claim arising out of surgery carried out in Belgium. In determining jurisdiction, the Court had to consider which of two competing reports as to the Belgian law of contract it preferred. One party’s expert complied with the requirements of CPR 35 and PD 35 and the other party did not comply in a wholesale way.

The Master commented [55] that the report “failed to comply with practically every requirement [of CPR PD 35.3.2]”. This was despite (or perhaps more likely because of) the expert being also the surgeon’s lawyer in Belgium. But the expert was impermissibly “acting as an advocate on behalf of his client’s position…He did not give any proper consideration to the evidence of Ms Spronken and did not fully consider the available documentary evidence with the inevitable result that he did not provide a balanced opinion covering the range of possible opinions. The most obvious illustration of this tendency was his abrupt observation that Mr Beer’s [opposing] report “contains a lot of mistakes and incorrect information.”

The upshot of these failings in the approach taken to drafting the report and matters of form were that the Master concluded that no weight could be placed on the evidence of that expert. A knockout blow for that party’s case on the point of foreign law because the failures of form revealed an expert who was not independent, transparent or complying with the duty to the Court, rather than to the instructing party.

Pal was perhaps an extreme example of non-compliance with CPR 35 by a foreign legal expert perhaps less familiar with the CPR than they ought to have been.

The take-away point for litigators is that when weighing up which expert(s) opinions to prefer, the Court will look at both the form and substance of that evidence. Trivial breaches of the rules about the content of reports are unlikely to weigh much in the balance or be too consequential. But it is unwise to overlook them for fear of disastrous consequences. Where the breaches of matters of form are extensive, this will undermine the opinions themselves. If the expert fails to understand and/or abide by the rules of form, how can the Court have any confidence that the opinions have been arrived at in a transparent and independent way, compliant with their duty to the Court? Ultimately, in the case under discussion, the Court’s confidence in the expert was completely undermined. This is worth having closely in mind the next time we are tempted to turn a blind eye to shortcomings in an expert’s approach to drafting a report.

The decision may be found here:

Charles Bagot QC


Charles Bagot KC

Call: 1997 | Silk: 2018


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