Supreme Court holds that courts must generally accept uncontroverted evidence

In TUI UK Ltd (Respondent) v Griffiths (Appellant) [2023] UKSC 48 the Supreme Court reaffirmed the general rule of evidence that a party who submits to the court that the opposing party’s witness evidence should not be accepted on a material point must firstly challenge that evidence by cross-examination during the trial, and cannot only raise the point during closing submissions. The purpose of this rule, as outlined in Browne v Dunn, is to ensure a fair trial by giving the witness an opportunity to respond to the challenge that their evidence is not accepted.

Background

The Claimant commenced proceedings against the defendant travel company, TUI, after he claimed to have suffered serious stomach upset during a package holiday to Turkey. At trial, the Claimant gave uncontested evidence about him almost exclusively consuming food and drink from the hotel at which he had been lodged. The Claimant also relied on an expert medical report which opined that, on the balance of probabilities, the likely cause of the Claimant’s medical issues was the food and drink served at the hotel. TUI did not cross-examine the Claimant’s expert at trial and did not provide any expert evidence of its own to oppose the Claimant’s expert. The evidence of the Claimant’s expert was therefore ‘uncontroverted’ in the sense that it was not in conflict with any other evidence led at trial and was not subjected to challenge by cross-examination. In closing submissions TUI challenged the expert evidence and persuaded the trial judge that deficiencies in the expert report meant the Claimant had failed to prove his case.

Challenging evidence under cross-examination

Following a series of overturned decisions in the lower appellate courts, the Supreme Court reviewed the previous authorities on evidence and reaffirmed the general rule, first established by the House of Lords in Browne v Dunn (1893): if a party seeks to challenge the evidence of a witness for the opposing party, whether expert or factual, then this should be done through cross-examination in order to achieve a fair trial by allowing the impugned witness an opportunity to explain or clarify their evidence. The Supreme Court clarified that the rule should not be applied rigidly however, and that there are exceptions, including:

• where the challenge is directed to a matter that is collateral or insignificant and fairness to the witness does not require an opportunity to answer or explain.
• where the evidence of fact is manifestly incredible and an opportunity to explain on cross-examination would make no difference.
• where there is a bold assertion of opinion in an expert's report without any reasoning to support it (although this does not include reasoning which appears inadequate and is open to criticism for that reason).
• where there is an obvious mistake on the face of an expert report.
• where the witnesses' evidence of the facts is contrary to the basis on which the expert expressed their view in the expert report.
• Where an expert has been given a sufficient opportunity to respond to criticism of, or otherwise clarify, their report – for example by answering questions put to the expert under CPR 35.6.

The Supreme Court found that none of the exceptions to the rule applied in the current case. While the evidence of the Claimant’s expert report was deficient insofar as it “left many questions unanswered…and is at a high level of generality” the Court held that “it is not irrational and there is no basis for concluding that [the expert] would not have explained his reasoning more clearly on cross-examination”. The Supreme Court therefore held that, in the absence of a proper challenge on cross-examination, it was unfair for TUI to submit detailed criticisms of the expert report in its closing submissions and for the trial judge to accept those submissions. The Claimant was held not to have had a fair trial as a result.

At the heart of the Supreme Court’s decision was the commitment to a fair trial and efficiency. If challenges to otherwise uncontroverted expert reports were allowed as part of closing submissions, that “would undermine the CPR’s arrangement for agreeing expert reports in advance of trial and narrowing down the areas of dispute.” Expert witnesses might also act defensively and produce overly complex reports which would add to the cost and length of legal proceedings.

Key takeaways

The Supreme Court’s decision makes clear that, subject to limited exceptions, a party who wants to convince the court not to accept their opponent’s evidence on a material point should generally challenge that evidence through cross-examination, not simply in closing submissions.

With thanks to Nisha Patel for her assistance in preparing this post.