In this case, Catherine McAndrew, a Senior Associate in the Insurance and Reinsurance team at CMS, comments on the Supreme Court’s decision in TUI Limited v Griffiths [2023] UKSC 48I, which was handed down on 29 November 2023.

The Supreme Court considered whether it was open to a court to reject evidence, in this case expert medical evidence, which was disputed but which had not been tested by cross-examination. The claimant’s expert report supported the causation of his injury, but the expert had not been required by the defendant to give oral evidence.  

The Supreme Court concluded that, despite certain deficiencies in the report, its dismissal by the trial judge in the absence of cross-examination had deprived the claimant of a fair trial. 


The claimant entered into a package holiday contract with the defendant for a 14 night, all-inclusive holiday to Turkey between 2 August and 16 August 2014.

On 4 August 2014, the claimant began to suffer from gastric symptoms. After two days, his symptoms were less severe and he began to improve, however they did not stop completely. On 7 August 2014, he travelled to a local town and ate at a local restaurant but was unable to eat much due to lack of appetite. On 13 August 2014, he was admitted to hospital where he was diagnosed with acute gastroenteritis. A stool sample showed multiple pathogens, both parasitic and viral. Though still feeling unwell, the claimant travelled home on 16 August 2014.

The claimant had eaten a fast food meal at the airport prior to commencing his holiday but, other than the meal he ate on 7 August, all food and drink was consumed at the hotel.

The claimant issued proceedings against the defendant in August 2017 for damages as a consumer under the Package Travel, Package Holiday and Package Tour Regulations 1992 and under Ss 4 and 13 of the Supply of Goods and Services Act 1982. The claim was allocated to the multi-track.

The defendant denied that the claimant’s illness was due to food and/ or drink consumed in the hotel and put him to proof as to the cause of his illness. The claimant obtained reports from a gastroenterologist, Dr Thomas, and a microbiologist, Professor Pennington. The defendant was given permission to rely on expert evidence from a gastroenterologist and a microbiologist, however (i) it failed to adduce evidence from a gastroenterologist in time and failed in its application for relief from sanctions; and (ii) it chose not to serve a report by a consultant microbiologist. The defendant therefore proceeded to trial without adducing any expert evidence. Further, the defendant’s witnesses of fact were not called or cross-examined, and so their evidence was discounted. The defendant did not seek to have the claimant’s expert Professor Pennington attend trial for cross-examination.

Lower Courts

In 2019, the trial judge (Her Honour Judge Truman) accepted the evidence of the claimant and his wife but made no findings of fact on the hygiene standards at the hotel. The judge recorded the evidence of the gastroenterologist in relation to diagnosis and prognosis. The microbiology report prepared by Professor Pennington and his replies to the defendant’s Part 35 questions were the only expert evidence on causation before the judge at trial. The defendant’s counsel criticised Professor Pennington’s report in his skeleton argument, served the afternoon before trial, and in closing submissions. Those criticisms formed the basis of the judge’s decision.

Professor Pennington’s report briefly considered the various possible causes of the claimant’s illness and concluded that, on the balance of probabilities, he had acquired his gastric illness following consumption of contaminated food or fluid at the hotel.

In finding against the claimant, the judge was critical of Professor Pennington’s report and responses provided in light of the written questions put to Professor Pennington under Civil Procedure Rule (“CPR”) Part 35.6 (which deals with expert evidence), but principally his failure to explain why he had concluded the source of infection was the hotel rather than other potential sources.

The claimant successfully appealed to the High Court. The judge considered that the case raised a fundamental question concerning the proper approach of the court towards uncontroverted evidence. The judge considered that two questions had to be answered:

  • whether the court is obliged to accept an expert’s uncontroverted opinion even if that opinion was an ipse dixit (a bare statement of opinion without adequate justification) and,
  • if the court is not so obliged, under what circumstances the court could justify rejecting the evidence.

The judge concluded that the court could reject an uncontroverted expert report if it were literally ipse dixit. However, what the court was not entitled to do, when faced with an uncontroverted expert report, was:

“…subject the report to the same kind of analysis and critique as if it was evaluation a controverted or contested report, where it has to decide the weight of the report in order to decide whether it was to be preferred to other, controverting evidence such as an expert on the other side or competing factual evidence. Once a report is truly uncontroverted, that role of the court falls away. All the court needs to do is decide whether the report fulfils certain minimum standards which any expert report must satisfy if it is to be accepted at all.”

Those minimum standards can be found in the Practice Direction to CPR 35.6, para 3.

The judge concluded that, although there were deficiencies with Professor Pennington’s report, it was not a bare ipse dixit and was sufficiently compliant with the minimum standards identified. The appeal was therefore allowed.

Court of Appeal

The defendant appealed to the Court of Appeal. Aplin LJ and Nugee LJ allowed the appeal, with Bean LJ dissenting.

Asplin LJ, delivering the leading judgment, found that the High Court was wrong to hold that, faced with an uncontroverted expert report, the court was not entitled to evaluate that report but instead simply consider if it met the minimum standards set out in the Practice Direction. Asplin LJ considered that the report failed to provide a range of opinion and lacked adequate reasoning in support of the expert’s conclusion. Nugee LJ agreed with Asplin LJ and held that trial judges had to evaluate all of the evidence, including evidence that is uncontroverted, and decide the weight to afford that evidence.

Bean LJ strongly dissented, describing as trite law that, in general, a party is required to challenge on cross-examination the evidence of any witness of the opposing party it wishes to submit to the court that that evidence should not be accepted. Bean LJ considered that the defendant should have cross-examined Professor Pennington if it wished to challenge his evidence and that a court should accept the evidence of an expert which is not subject to cross-examination (uncontroverted). Ben LJ considered that leaving challenges until closing submissions was litigation by ambush and that the claimant had not been afforded a fair trial in the circumstances.

The claimant appealed to the Supreme Court.

Decision of the Supreme Court

The claimant was successful on appeal to the Supreme Court.

The court considered that making closing submissions attacking an expert’s evidence was neither fair nor sufficient. Professor Pennington’s report may have been “terse” and lacking in certain respects, but it did provide reasonable justification for the expert’s conclusion on causation. It was not a mere expression of opinion. His evidence ought to have been tested by cross-examination.

With reference to a statement in Phipson on Evidence, that a party is required to challenge on cross-examination the evidence of any witness of the opposing party if it wishes to submit to the court that that evidence should not be accepted, the court found that the claimant had been denied a fair trial. Maintaining the fairness of the trial included ensuring fairness to the witness whose evidence was being impugned and enabling the judge to make a proper assessment of all the evidence. Cross-examination gave the witness the opportunity to explain or clarify his or her evidence. That principle was not limited to cases in which the witnesses’ honesty was being impugned, but rather was of general application. 

It is important, however, to recognise that the Supreme Court did not find this to be an absolute rule. It was to be regarded as a general principle, but there would be circumstances in which it should not apply. Examples provided by the court were:

  • The matter to which the challenge is directed is collateral or insignificant and fairness to the witness does not require there to be an opportunity to answer or explain.
  • The evidence of fact is manifestly incredible, and an opportunity to explain on cross-examination would make no difference.
  • The expert report contains a “bold assertion of opinion” without reasoning to support it (“bare ipse dixit”), although this should be distinguished from reasoning which appeared inadequate and was open to criticism for that reason.
  • An obvious mistake on the face of the expert report.
  • The witnesses’ evidence of the facts are contrary to the basis on which the expert expressed his or her view in the expert report.
  • Where an expert has been given a sufficient opportunity to respond to criticism of, or otherwise clarify his or her report, for example, through questions under CPR Part 35.6.
  • A failure to comply with the requirements of CPR PD 35.

It was found that none of the exceptions applied in this matter. Although CPR Part 35 questions had been put to the expert, they were not sufficient to properly put the claimant on notice of the challenge being made to the evidence. They had not provided opportunity for the expert to explain his evidence, sufficient to negate the need for cross-examination.

In dismissing the defendant’s argument that requiring cross-examination would lead to a disproportionate increase in legal costs, the Supreme Court observed that, in low value cases, where deficient medical evidence is relied upon, a defendant had the opportunity to address the deficiencies through targeted questions under CPR Part 35, clearly setting out the challenges and providing sufficient opportunity for the expert to respond, thereby keeping the costs associated with defending matters of this nature proportionate. 


The Supreme Court has clarified the way in which disputed evidence, not only expert evidence, should be handled. Parties must challenge clearly and allow sufficient opportunity for response.

This is consistent with the requirement that cases are dealt with justly. Under the CPR, however, cases must not only be dealt with justly but also at proportionate cost. Requiring experts in low value claims to give oral evidence at trial significantly increases costs. The clear instruction from the Supreme Court is that parties must ensure that full and effective use is made of any questions under CPR Part 35 in such cases, rather than raising challenges at the end of trial.

The exceptions cited by the Supreme Court are wide-ranging, however. It is not at all difficult to imagine that arguments will arise over whether, for example, an expert report contains the bare assertion of opinion without adequate justification, or whether a party’s questions posed under CPR Part 35 provided an expert with adequate opportunity to address criticisms of the evidence.

As is so often the case, firmly closing one area of dispute may prove to result in the creation of new issues for parties to fall out about. We suspect that the ripples from TUI Limited v Griffiths will run on for some time to come.