Griffiths v. TUI UK Limited: Evidence, Challenge and Fairness

3 January 2024 by Edward Waldegrave

Overview

The central question facing the Supreme Court in Griffiths v TUI UK Limited [2023] UKSC 48 concerned the extent to which a party must put criticisms of a witness’ evidence to him in cross-examination. The Supreme Court made clear that the general rule in civil cases is that a party is required to challenge by cross-examination the evidence of any witness (whether factual or expert) if he wishes to submit that the evidence should not be accepted by the court. Importantly, this rule is not confined to allegations that the witness is dishonest. The rule is, however, a flexible one; it will not always be necessary for every point of challenge to be put to a witness, and in some cases (such as where evidence is “manifestly incredible”) it may not apply at all. Although the Supreme Court gave a conceptually clear answer to the question before it, difficult practical issues are likely to continue to arise for trial advocates who wish to challenge factual or expert witness evidence.

Factual Background

The dispute in TUI arose from simple facts. Mr. Griffiths went with his family on a TUI package holiday to Turkey. As well as flights, the holiday package included full-board hotel accommodation. The family travelled to Turkey on 2 August 2016. Immediately before flying, Mr. Griffiths ate at the Burger King in Birmingham Airport. On 4 August he fell ill, suffering from stomach cramps and diarrhoea. For two days he was confined to his room. After that, his condition improved slightly. On 7 August Mr. Griffiths travelled to the local town to purchase medication. While there, Mr. Griffiths went to a local restaurant, but ate little. On 10 August, Mr. Griffiths’ condition worsened and on 13 August he was admitted to hospital. There he was diagnosed with acute gastroenteritis, and a stool sample was taken. Although he continued to feel unwell, he was able to travel back to the UK as planned on 16 August. Mr. Griffiths’ symptoms persisted and it was noted by the Supreme Court that they were likely to be permanent.

The Trial and the Expert Evidence

In August 2017 Mr. Griffiths brought a claim in the County Court against TUI for damages. The claim was brought on the basis that Mr. Griffiths was made ill by food he had eaten at the hotel in Turkey. TUI defended the claim. In particular, it denied that Mr. Griffiths’ illness had been caused by food or drink which he had consumed at the hotel.

At trial, Mr. Griffiths relied in support of his case on causation on a report from a microbiologist, Professor Pennington. Professor Pennington provided an expert report. In the conclusion of this report, Professor Pennington set out his view that, “on the balance of probabilities”, Mr. Griffiths’ illness had been caused by the consumption of food or drink at the hotel.

TUI asked some written questions in relation to Professor Pennington’s report under rule 35.6 of the CPR. It did not, however, lead any expert evidence of its own. It also did not require Professor Pennington to attend the trial for cross-examination. In these respects, Professor Pennington’s evidence was “uncontroverted”. However, in closing submissions counsel for TUI criticised various aspects of Professor Pennington’s evidence. In particular, TUI contended that Professor Pennington had not addressed and excluded possible alternative causes of Mr. Griffiths’ illness. These included the possibilities that (i) the illness had been caused by the food which Mr. Griffiths consumed at Burger King in Birmingham Airport; and (ii) Mr. Griffiths had in fact been infected twice, with the second infection being caused by the food he had eaten in the local town on 7 August 2016. Together with other criticisms which the Judge made of Professor Pennington’s evidence, this led the Judge to conclude that Mr. Griffiths had not proved his case on causation. Accordingly the claim was dismissed.  

Although the Judge decided the case in TUI’s favour, she decided that (had she found for Mr. Griffiths) she would have awarded compensation of £29,000.

The High Court and the Court of Appeal

Mr. Griffiths appealed to the High Court, where the case was heard by Mr. Justice Martin Spencer. He took the view that HHJ Truman had not been entitled to discount Professor Pennington’s evidence as she had done. Martin Spencer J’s view was that, provided that an expert report met certain “minimum standards”, a trial judge was not entitled to discount the weight to be attached to it in circumstances in which it had not been controverted by other expert evidence or challenges put in cross-examination. Although Martin Spencer J accepted that there were “serious deficiencies” in Professor Pennington’s report, his conclusion was that it met the relevant “minimum standards”. On the basis that it was uncontroverted by other expert evidence or challenge in cross-examination, the trial judge had not been entitled to attach reduced weight to its conclusions. Accordingly, Mr. Griffiths’ appeal was allowed.

TUI then appealed to the Court of Appeal. The leading judgment was given by Lady Justice Asplin, with whom Lord Justice Nugee agreed. Asplin LJ took the view that TUI’s appeal should be allowed, concluding that the Judge had been entitled to evaluate Professor Pennington’s report notwithstanding the absence of contradictory expert evidence or challenge in cross-examination. In the Court of Appeal, counsel for Mr. Griffiths submitted that it was unfair for an expert’s evidence to be challenged only in closing submissions, when the expert had no opportunity to defend his position. Lady Justice Asplin accepted that this submission in relation to cases where the expert’s credibility was in issue, but considered that no such rule applied in a case where the witness’ honesty was not being impugned. Nugee LJ agreed that, as a matter of principle, a trial judge is entitled to evaluate evidence including on the basis of criticisms only advanced in closing submissions.

Lord Justice Bean strongly dissented from these views. He took the view that TUI’s omission to challenge Professor Pennington’s evidence until closing submissions meant that Mr. Griffiths had not had a fair trial of his claim. Rather “litigation by ambush” had been permitted.

The Supreme Court’s Decision

Mr. Griffiths appealed to the Supreme Court against the Court of Appeal’s decision. The only reasoned judgment was given by Lord Hodge. He identified the key question of principle which the appeal raised as concerning the scope of the rule that “a party should challenge by cross-examination evidence that it wishes to impugn in its submissions at the end of the trial”. In particular, Lord Hodge thought that it was necessary to decide whether this rule applied to “attacks in submissions… on the reasoning of an expert witness”.

In answering these questions Lord Hodge began by emphasising that the role of an expert is to “assist” the trial judge in relation to matters of “specialised knowledge”, and that the judge remains the decision-maker. Lord Hodge therefore accepted that it is, in principle, for the judge to assess the adequacy and persuasiveness of an expert’s evidence. However, Lord Hodge stressed that this exercise is one which must be conducted in a way which is fair, and that the precise nature of the judge’s role in any particular case will depend on the way in which the issues are framed by the parties.

Lord Hodge proceeded to identify that it is a central requirement of fairness that, if a party wishes to submit to the court that the evidence of a witness should not be accepted on a particular point, then the witness should be challenged on the point in cross-examination. He explained that this rule had been established by a line of case law which started with early 19^th century decision of the House of Lords in The Queen’s Case (1820) 2 Brod & Bing 284 (which concerned the trial of Queen Caroline for adultery). Counsel for TUI sought to confine the principle to be derived from this line of case law to circumstances in which it was submitted that a witness was dishonest (or had acted in bad faith). Lord Hodge stated that he could see “no rational basis” for so confining the rule. Moreover, he identified judicial comments to the effect that a witness should be given an opportunity to “explain” his evidence where some criticism is made of it. For example, in Browne v. Dunn (1893) 6 R. 67, Lord Halsbury said that “nothing would be more absolutely unjust than not to cross-examine witnesses upon some evidence which they have given, so as to give them notice, and to give them an opportunity of explanation… to ask the jury afterwards to disbelieve what they have said” (emphasis added).

On the basis of his survey of the case law, and his consideration of the principles which underpinned it, Lord Hodge concluded his discussion of the law by identifying eight propositions. In summary, these were as follows:

• The general rule in civil cases is that a party is required to challenge by cross-examination the evidence of any witness (whether factual or expert) which he wishes to submit should not be accepted by the Court.
• This rule is founded on the requirements of fairness in an adversarial system of litigation.
• The rule exists in order to prevent unfairness to the party who adduced the evidence in question.
• However, the rule exists also to prevent unfairness to the witness himself. In the case of expert evidence, a witness may suffer considerable prejudice if his evidence is the subject of a successful challenge on the basis of inaccuracy or inadequacy, and it is necessary that he should have a chance to answer any such challenges.
• A further reason for the existence of the rule is that it enables the Judge properly to assess the evidence. The rule therefore serves the “integrity of the court process itself”.
• The rule serves a particularly important function where a party wishes to submit that a witness has been dishonest in giving his evidence. It is not, however, confined to “dishonesty” cases.
• While important, the rule is also to be applied with flexibility. In particular, it may not be possible or proportionate (especially in complex litigation) for every single point of criticism to be put to a witness in cross-examination.
• Finally, there are cases in which the rule may not apply. Lord Hodge identified seven such situations. These include cases where the point in question concerns a “collateral issue”, where it is “manifestly incredible”, where an expert opinion has been advanced without being supported by any reasoning, where there is an obvious mistake in an expert report, and where the expert has given evidence on the basis of an incorrect factual picture. Lord Hodge also identified that an expert may be given a sufficient opportunity to respond to criticisms otherwise than by being challenged in cross-examination; for example, the requirements of fairness may be satisfied by written questions being asked under CPR rule 35.6.

Having identified the principles summarised above, Lord Hodge considered their application to the facts of the case to be straightforward. He concluded that it had been unfair for TUI to criticise Professor Pennington’s report as it had done without giving him the chance to answer those criticisms in cross-examination, and unfair for the trial judge to accept them in such circumstances. This was the case even though the criticisms did not go to Professor Pennington’s honesty. Lord Hodge proceeded to allow Mr. Griffiths’ appeal.

Comment

The Supreme Court’s decision in Griffiths v. TUI UK Limited is of significance principally because it provides clear guidance on the scope of the well-established rule that a witness should be given an opportunity to answer criticisms of his evidence. It makes clear that the rule does not apply only in relation to dishonesty allegations, and in particular that it may apply in relation to alleged deficiencies (falling short of dishonesty) in expert evidence.

In some respects, the question for the Supreme Court may be seen as having concerned the relative importance of (i) the requirements of fairness (which clearly favour the witness being able to answer challenges to his evidence); and (ii) the unfettered ability of the trial judge to evaluate evidence, including the ability to dismiss or discount it on the basis of points not put in cross-examination. Lord Hodge answered this question in favour of the former consideration; the judge’s right and ability to assess the totality of the evidence before him is secondary to the requirements of procedural fairness.

In these respects the Supreme Court’s decision in TUI may be seen as bringing welcome conceptual clarity. In practical terms, however, practitioners are likely to continue to face difficult questions as to how they should discharge the requirements of fairness when they wish to challenge the evidence given by a factual or expert witness. Lord Hodge clearly recognised that his articulation of the relevant principles represents a counsel of perfection which will often not be achievable, especially in cases in which resources are limited and/or the time for cross-examination is restricted. In all cases in which the evidence of a witness is the subject of challenge, opposing advocates will need to ensure that they do enough to discharge the requirements of fairness which the Supreme Court has identified, while also seeking to proceed in a pragmatic, flexible and efficient manner – conscious of the considerable dangers inherent in failing properly to put their case. This is a balancing exercise which, in many cases, is unlikely to be straightforward.

Edward Waldegrave is a barrister at 1 Crown Office Row.