- Parties in civil cases must challenge opposing expert evidence through cross-examination to ensure a fair trial
- Criticisms of an expert’s report should not be reserved for closing submissions if they could have been addressed during the trial
- The need for cross-examination depends on the specific circumstances of each case, with the focus on overall fairness and proportionality
KEY TAKEAWAYS:
In our recent article covering litigation privilege and its reach to expert support (available here) we considered whether litigation privilege may be claimed over all the correspondence with a third party expert / a instructing party, concluding that it was not (for the reasons given in Kyla Shipping Co Ltd & Anor v Freight Trading Ltd & Ors [2022] EWHC 376 (Comm) (22 February 2022).
Relevant to that conclusion is the more recent question which the Supreme Court (in TUI v Griffiths [2023] UKSC 48) (the "Decision") had to consider, namely how expert evidence in civil proceedings should be treated in circumstances where the expert report is not challenged whether in writing, via a counter expert report or in cross-examination. There is no/similar authority on this subject in the Bailiwick of Guernsey, and it is likely that the decision will be persuasive if an issue of identical/similar nature comes before a Court in Guernsey.
The Decision concerned a tour operator TUI (the "Company") and its customer, Mr Griffiths, who fell sick during his all-inclusive holiday purchased from and provided by the Company. Mr Griffiths sued the Company for breach of contract and relied on expert evidence to prove the cause of his sickness, which was likely to be permanent. Before the trial judge the issue of causation was dealt with by the only expert who gave an uncontroverted expert report and opined that Mr Griffiths illness had been caused by the food and drink consumed at the hotel. The Company did not file its own expert evidence on the central question of causation or seek to cross-examine Mr Griffith's expert witness at trial, but rather, in closing submissions, criticised the expert report as poorly reasoned, incomplete, insufficient, unreliable and that it failed to exclude other possible causes of the illness.
Appeal to the Supreme Court
During the appeal the Supreme Court carefully considered recent authorities on the treatment of expert evidence. Of particular interest to the Supreme Court was Browne v Dunn ([1893] 6 R 67) ("Browne v Dunn") and Phipson on Evidence (20th ed.).
In Browne v Dunn, Lord Herschell LC stated his understanding of the rule(s) surrounding the treatment of expert evidence, and said, inter alia, that it is "… absolutely essential to the proper conduct of a case, where it is intended to suggest that a witness is not speaking the truth on a particular point, to direct his attention to the fact by some questions put in cross-examination…" and that "…if you intend to impeach a witness you are bound whilst he is in the box, to give him an opportunity of making any explanation which is open to him; and, as it seems to me, that is not only a rule of professional practice in the conduct of a case, but is essential to fair play and fair dealing with witnesses."
This has become commonly known as the Browne v Dunn rule.
In Phipson on Evidence (20th ed.) it is explained that in civil proceedings a party is required to "challenge in cross-examination the evidence of any witness of the opposing party" on a material point which they seek to submit should not be accepted. Phipson also provides that "this rule serves the important function of giving the witness the opportunity of explaining any contradiction or alleged problem with his evidence".
Having considered, inter alia, Browne and the explanations in Phipson, the Supreme Court reached the following key conclusions in relation to how expert evidence in civil proceedings should be treated in circumstances where the expert report is not challenged:
a. The rule in civil cases 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 he or she wishes to submit to the court should not be accepted.
b. The general approach in (a) above extended to both witnesses as to fact and expert witnesses.
c. In an adversarial system of justice in the UK (in which Guernsey is similar), the purpose of the rule is to make sure that trial is fair.
d. Maintaining the fairness of the trial includes:
f. The application of the rule depends upon the circumstances of the case as the criterion is the overall fairness of the trial, thus, where it would be disproportionate to cross-examine at length or where the trial judge has set a limit on the time for cross-examination, those circumstances would be relevant considerations in the court’s decision on the application of the rule.
For these reasons, among others, the Supreme Court held that both the trial judge and the majority of the Court of Appeal "erred in law in a significant way." The trial judge did not consider the effect on the fairness of the trial of the Company's failure to cross-examine Mr Griffith's expert. In accepting the Company's criticisms of Mr Griffith's expert's report without giving the expert an opportunity to explain his reasoning in cross-examination, the trial judge had denied Mr Griffiths a fair trial.
The Court went on to find that, on the evidence, Mr Griffiths had established his case on causation on the balance of probabilities and in the absence of proper challenge on cross-examination, it was not fair for the Company to advance the criticisms that it did in its submissions or for the trial judge to accept those submissions.
Final comments
The Supreme Court decision reaffirms the importance of the rule in Browne v Dunn, that a party who submits that the court should not accept an opponent's witness evidence on a material point, such as causation in this instance, must challenge that evidence (whether factual or expert) in cross-examination. This decision also provides important clarification for parties in litigation making it clear that the principle of fairness in relation to expert evidence means a party should not entirely reserve its criticisms of an expert’s evidence for closing submissions, especially in circumstances where a party had opportunities to challenge the evidence throughout the proceedings and trial. The principle of fairness requires experts be given the opportunity to explain or clarify their reasoning, especially with uncontroverted evidence.
While the Supreme Court's judgment clarified that this is not a hard and fast rule, and every case will be assessed by the individual facts and circumstances, it did provide several non-exhaustive scenarios in which a party may not be required to challenge the evidence of the opposing party via cross-examination in order to submit that such evidence should not be accepted.
The Decision concerned a tour operator TUI (the "Company") and its customer, Mr Griffiths, who fell sick during his all-inclusive holiday purchased from and provided by the Company. Mr Griffiths sued the Company for breach of contract and relied on expert evidence to prove the cause of his sickness, which was likely to be permanent. Before the trial judge the issue of causation was dealt with by the only expert who gave an uncontroverted expert report and opined that Mr Griffiths illness had been caused by the food and drink consumed at the hotel. The Company did not file its own expert evidence on the central question of causation or seek to cross-examine Mr Griffith's expert witness at trial, but rather, in closing submissions, criticised the expert report as poorly reasoned, incomplete, insufficient, unreliable and that it failed to exclude other possible causes of the illness.
Appeal to the Supreme Court
During the appeal the Supreme Court carefully considered recent authorities on the treatment of expert evidence. Of particular interest to the Supreme Court was Browne v Dunn ([1893] 6 R 67) ("Browne v Dunn") and Phipson on Evidence (20th ed.).
In Browne v Dunn, Lord Herschell LC stated his understanding of the rule(s) surrounding the treatment of expert evidence, and said, inter alia, that it is "… absolutely essential to the proper conduct of a case, where it is intended to suggest that a witness is not speaking the truth on a particular point, to direct his attention to the fact by some questions put in cross-examination…" and that "…if you intend to impeach a witness you are bound whilst he is in the box, to give him an opportunity of making any explanation which is open to him; and, as it seems to me, that is not only a rule of professional practice in the conduct of a case, but is essential to fair play and fair dealing with witnesses."
This has become commonly known as the Browne v Dunn rule.
In Phipson on Evidence (20th ed.) it is explained that in civil proceedings a party is required to "challenge in cross-examination the evidence of any witness of the opposing party" on a material point which they seek to submit should not be accepted. Phipson also provides that "this rule serves the important function of giving the witness the opportunity of explaining any contradiction or alleged problem with his evidence".
Having considered, inter alia, Browne and the explanations in Phipson, the Supreme Court reached the following key conclusions in relation to how expert evidence in civil proceedings should be treated in circumstances where the expert report is not challenged:
a. The rule in civil cases 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 he or she wishes to submit to the court should not be accepted.
b. The general approach in (a) above extended to both witnesses as to fact and expert witnesses.
c. In an adversarial system of justice in the UK (in which Guernsey is similar), the purpose of the rule is to make sure that trial is fair.
d. Maintaining the fairness of the trial includes:
- fairness to the party who has adduced the evidence of the impugned witness;
- fairness to the witness whose evidence is being impugned, whether on the basis of dishonesty, inaccuracy or other inadequacy; and
- enabling the judge to make a proper assessment of all the evidence to achieve justice in the cause;
f. The application of the rule depends upon the circumstances of the case as the criterion is the overall fairness of the trial, thus, where it would be disproportionate to cross-examine at length or where the trial judge has set a limit on the time for cross-examination, those circumstances would be relevant considerations in the court’s decision on the application of the rule.
For these reasons, among others, the Supreme Court held that both the trial judge and the majority of the Court of Appeal "erred in law in a significant way." The trial judge did not consider the effect on the fairness of the trial of the Company's failure to cross-examine Mr Griffith's expert. In accepting the Company's criticisms of Mr Griffith's expert's report without giving the expert an opportunity to explain his reasoning in cross-examination, the trial judge had denied Mr Griffiths a fair trial.
The Court went on to find that, on the evidence, Mr Griffiths had established his case on causation on the balance of probabilities and in the absence of proper challenge on cross-examination, it was not fair for the Company to advance the criticisms that it did in its submissions or for the trial judge to accept those submissions.
Final comments
The Supreme Court decision reaffirms the importance of the rule in Browne v Dunn, that a party who submits that the court should not accept an opponent's witness evidence on a material point, such as causation in this instance, must challenge that evidence (whether factual or expert) in cross-examination. This decision also provides important clarification for parties in litigation making it clear that the principle of fairness in relation to expert evidence means a party should not entirely reserve its criticisms of an expert’s evidence for closing submissions, especially in circumstances where a party had opportunities to challenge the evidence throughout the proceedings and trial. The principle of fairness requires experts be given the opportunity to explain or clarify their reasoning, especially with uncontroverted evidence.
While the Supreme Court's judgment clarified that this is not a hard and fast rule, and every case will be assessed by the individual facts and circumstances, it did provide several non-exhaustive scenarios in which a party may not be required to challenge the evidence of the opposing party via cross-examination in order to submit that such evidence should not be accepted.