Jonathan Lindfield of our Personal Injury team considers the Supreme Court’s judgment in the case of Griffiths v TUI [2023] UKSC 48 concerning “uncontroverted” expert evidence and the practical implications of the decision in day-to-day litigation.

The Supreme Court unanimously agrees with MC Hammer – “U can’t touch this”.

The Supreme Court today handed down its long-awaited judgment in the case of Griffths v TUI [2023] UKSC 48. It is a thorough, important, and helpful statement (or, depending on one’s view, re-statement) of the laws and rules of evidence, what must be put to a witness before that evidence can be challenged in closing submissions, and the limits on any Judge’s power to dismiss relevant evidence which has not been challenged (or challenged sufficiently) at trial. At the heart of the judgment is the Court’s assessment of what it means for the parties to have a fair trial.

Facts and the Judgments below – in brief

This case concerned Mr Griffiths, who claimed he had contracted food poisoning whilst on holiday in Turkey. He made a claim pursuant to the Package Travel, Package Holidays and Package Tours Regulations 1992. In his claim, he was supported by expert evidence of a microbiologist, Professor Pennington, on causation of his illness, who said that it was more likely than not to have been the food at the hotel which caused his illness. The claim was allocated to the multi-track and the defendant was given permission to obtain its own microbiologist, but the defendant declined to do so. The defendant put Part 35 questions to Professor Pennington, who did not change his opinion.

At trial, without requiring Professor Pennington to attend for cross-examination, the defendant sought to criticise his report, because it had, amongst other criticisms, failed adequately, said the defendant, to rule out other sources of illness, as required by Wood v TUI [2017] EWCA Civ 11. Those points were taken, for the first time, in the defendant’s skeleton argument and in closing submissions (a point which the court accepted). The defendant invited the court to dismiss Professor Pennington’s evidence on those bases.

At first instance, the trial Judge (Her Honour Judge Truman), dismissed the evidence of Professor Pennington, finding that, essentially, it didn’t do a good enough job. She declined, on the basis of the defendant’s criticisms, to accept his findings, and therefore dismissed the claimant’s claim on causation grounds. Without Professor Pennington’s evidence, the claimant couldn’t establish what caused his illness. The claimant appealed.

In the High Court, Mr Justice Martin Spencer allowed the claimant’s appeal.

The Court of Appeal, by majority (Asplin and Nugee LJ, Bean LJ dissenting) allowed the defendant’s appeal, finding that the Judge was entitled to dismiss the evidence.

For a full summary of the facts of the case and the judgments below, please see Jimmy Barber’s helpful article here.

The Supreme Court Judgment

The judgment, delivered by Lord Hodge (and unanimously agreed by a panel of 5), carries out a thorough review on the authorities and principles with respect to the rules of evidence, the so-termed “rule in Browne v Dunn”), the adversarial nature of trials in this jurisdiction, and, ultimately, fairness to the parties. It is not necessary to spell it all out here, but it bears useful and interesting reading. The import of the judgment is in the conclusions.

Lord Hodge summed up his conclusions on the general laws, principles, and rules of evidence at paragraph 70 of his judgment. He said, in terms:

  • That the general rule is that a party is required to challenge by cross-examination the evidence of any witness of the opposing party on a material point which they submit should not be accepted. That applies to lay and expert witnesses.
  • That the parties frame the decisions that a Judge needs to make. It’s adversarial as a process, and being adversarial makes it fair.
  • The rationale of the rule (i.e. fairness) includes fairness to the party who has called the evidence of the impugned witness.
  • Maintaining fairness includes fairness to the person giving the evidence – particularly experts who have a reputation to think about.
  • Fairness means enabling Judge to make a proper assessment of all the evidence.
  • Cross examination enables the witness to explain or clarify their evidence. That is really important when you’re calling a witness dishonest, but is not confined to those cases.
  • The rule should not be applied inflexibly (Lord Hodge specifically referred to Phipson on Evidence para 12.12, which I shall not repeat here). Its application depends upon the circumstances of the case, the criterion is overall fairness of the trial. For example, where it is disproportionate to cross-examine at length or where the judge has set a limit on cross-examination, those circumstances are relevant to a court’s decision re the application of the rule.
  • There are circumstances where the rule doesn’t apply. He suggests the following (non-exhaustive) examples (quoting from other authorities in places), drawn from paragraphs 61-69 of the judgment:
  • Where the challenge is collateral or insignificant
  • Where the evidence of fact is manifestly incredible and opportunity to cross-examine would make no difference
  • Where there has been a bald assertion of expert opinion without any reasoning to support it, otherwise known as “a bare ipse dixit” – he qualified that evidence which appears inadequate and is open to criticism is not the same as a bare ipse dixit.
  • An obvious mistake on the face of an expert report, where the report was illogical or inherently inconsistent, something “patently absurd”.
  • Where the witnesses’ evidence of the facts may be contrary to the basis on which the expert expressed his or her view in the expert report – where the report is “based on an incorrect or incomplete history, or where the assumptions on which it is founded are not established”.
  • Where an expert has been given an opportunity to respond to criticism of or otherwise clarify his or her report beforehand. Lord Hodge gives the example of an expert having “focused questions in the written CPR 35.6 questions of the opposing party and fails to answer them satisfactorily” – then the Judge might find that they don’t need to be challenged further.
  • Failure to comply with Part 35 (although he says you should probably ask for directions first before challenging it at trial)

Having set out those general rules, he applied them to the facts of this case. In this case, he found that in circumstances where:

  • The defendant had permission for their own microbiologist and chose not to get one.
  • The Part 35 questions which the defendant had put were “not focused”, didn’t clearly set out the matters which Counsel relied on in closing to undermine the evidence, and “didn’t put the expert on notice of those criticisms”.
  • Professor Pennington wasn’t called to give evidence.
  • The challenge to the medical evidence was not foreshadowed until skeletons.
  • The Judge had accepted the evidence given by the lay witnesses.

All put together, meant there had been no sufficient challenge to the report such that the Judge was entitled effectively to ignore it and to find that the expert was wrong. In fact, he found that the Judge at first instance and the majority of the Court of Appeal had erred in a “significant way”.

That didn’t mean that he didn’t have any criticism of the report. Lord Hodge said, of that expert report “it was terse and cold and should have included far more expansive reasoning. It left many questions unanswered. But it was far from a bare ipse dixit”. The expert’s reasoning as to why it wasn’t the meal Mr Griffiths ate in the town, or the airport, rather than the hotel was “at a high level of generality but is not irrational and may have been proportionate in the circumstances of the claim” and “there is no basis for concluding that the expert would not have explained his reasoning more clearly if challenged on cross-examination”. However, the fact that the reasons were, in the defendant’s view, not good enough, was very different to saying that it was wrong and could be dismissed without challenge.

Further, Lord Hodge did address the Defendant’s concerns re proportionality in low value cases. He found that “a defendant may be able to adopt more economic ways of testing the expert’s evidence. It is important and consistent with the ethos of the CPR that there be a proportionate use of resources in the pursuit and defence of such claims. A defendant can ask focused Part 35 questions which articulate clearly the challenge or challenges on which the defendant wishes to make and give the expert the opportunity to explain his or her evidence in response to those challenges, thereby obviating the need to seek the expert’s attendance for cross-examination”.

So, pulling that all together, the takeaway points are:

  • There is no difference between a Judge finding that “the claimant doesn’t come up to proof” in dismissing the conclusions of an expert and finding that the expert is wrong. A Judge must accept or reject the evidence. If they are to reject it, it must be on the basis of legitimate challenge.
  • If you want to challenge what any witness says, lay or expert, on a matter which is central to the case, at trial, you must give them an opportunity to respond to that challenge. That requirement is not confined to issues of honesty.
  • You do not always have to cross-examine an expert to achieve that aim, but if you are not going to call them for cross-examination, any Part 35 questions need to be focused, and articulate clearly the challenge or challenges you wish to make to that expert.
  • If you do not challenge the evidence presented (i.e. it is “uncontroverted”), then it must be accepted by the court unless one of the exceptions to the rule applies (the most obvious ones in everyday practice being where there is a “bare ipse dixit” and where the factual basis upon which the report is written is inaccurate (for example, an expert who is not told about previous accidents or has the circumstances of the accident wrong)).
  • Real care is needed in deciding whether to challenge an expert or not. If your thoughts are “those reasons are rubbish”, then unless they are illogical or patently absurd, you need to challenge it.
  • It is not good enough to leave criticism of an expert report to closing submissions at trial. It must be foreshadowed.

Lord Hodge doesn’t suggest what adequate Part 35 questions would have been, but it is implicit in his judgment that they ought to have directly addressed the criticisms made in closing. Often defendants do not wish to ask Part 35 questions in lower-value claims as it is perceived that it runs the risk of a claimant “shoring up” their case. However, unless you have good reason to think you can undermine the factual basis on which the report was written (and the expert having access to medical records is, to my mind, likely to be an interesting battleground if the challenge is “you weren’t told about previous accidents”, if they do in fact appear in the records), then Part 35 questions will have to be asked if causation is to be challenged.

Unfortunately, what the judgment does somewhat overlook in its assessment of the costs of litigation, is the fact that Counsel’s involvement in drafting Part 35 questions is not covered by either the fast or intermediate track costs regimes. It may be something for the CPRC to consider, but for now, it seems to me to be money well-spent given the importance of the same going forward.

This summary is no substitute for reading the Judgment, but hopefully spells out the takeaway points. For any additional questions, get in touch.