In June 2015, I wrote an article on a case about the importance of an expert’s conflict of interest, in which the Court had to consider both the procedural and substantive implications of an expert’s conflict that emerged during the trial. The High Court had concluded that, although the defendant’s expert’s evidence had not been ruled as inadmissible, the judge’s confidence in that expert had been so undermined that he preferred the claimant’s expert and the claimant succeeded.

The case in the High Court

The case in the High Court revolved around whether any reasonably competent neuroradiologist in 1999 should have seen and reported a cerebral aneurysm on an MRI scan, such that the failure of the defendant to do so was in breach of duty. Causation was not disputed at trial and it was accepted by the defendant that, if the aneurysm had been diagnosed in 1999, it would have been clipped successfully and the claimant would have returned to work in 2-3 months.

The claimant’s neuroradiologist expert was Dr Paul Butler from Bart’s Hospital in London. The defendant’s equivalent expert was Dr Andrew Molyneux, a consultant neuroradiologist in Staffordshire. His CV served with his report stated that he had been a consultant neuroradiologist in Oxford between 1979 and 2004, following which he had moved to Staffordshire. His CV did not mention Dr Barker, the defendant. Dr Barker’s CV revealed that between 1984 and 1989 he had been a Registrar in Oxford on the radiology training scheme; in 1989 he became a Senior Registrar in Oxford; and he then became a Consultant in Southampton in 1991. His CV did not mention Dr Molyneux. However, during cross-examination at trial, it emerged that there was a very substantial connection between Dr Molyneux and Dr Barker, in that:

  • Dr Molyneux had trained Dr Barker during the latter’s 7 years of specialist radiology training between 1984 and 1991, and in particular he had trained him for 2½ years as a Senior Registrar in interventional neuroradiology between 1989 and 1991;
  • They had worked together closely over this substantial period;
  • They had written a paper together for an international radiology symposium;
  • They might have co-operated on other papers, but Dr Molyneux could no longer specifically recall whether that was the case;
  • Dr Molyneux had helped Dr Barker to obtain two foreign fellowships;
  • They had been officers together on the committee of the British Society of Radiologists;
  • Dr Barker said that Dr Molyneux had guided and inspired his practice and had helped him become a consultant in Southampton; and,
  • Dr Barker had recommended that Dr Molyneux be the defence expert.

The High Court judge (Mr Justice Kenneth Parker) had been troubled by both the connection, and the nature and extent of the connection, between the defence expert and the defendant, as it involved a “mentor” and “tutelage” role. He had further been troubled by the fact that Dr Molyneux referred to the defendant as “Simon” in cross-examination in an unguarded moment, which he felt showed traces of the bond between them remaining. The judge had also been troubled by the fact that the connection and its extent had not been disclosed by the defence team before trial. Not only was this practically and procedurally problematic, but it created an inference of a deliberate default. Ultimately, the judge did not rule Dr Molyneux’s evidence as inadmissible, as that would fatally undermine the defence’s case (although he was a whisker away from doing so), but his confidence in Dr Molyneux had been “very substantially undermined”, such that he preferred Dr Butler’s evidence, and accordingly the claimant succeeded.

The case on appeal

The case was heard in the Court of Appeal by Lord Justice Irwin, giving judgment, with Lady Justice Black and Lord Justice Henderson.

The defence’s appeal was advanced on the following Grounds:

  1. The learned judge failed correctly to identify and formulate the applicable Bolam test in evaluating the actions of the defendant.
  2. The judge failed to apply the Bolam test to the expert evidence relating to the defendant’s response to the 1999 imaging.
  3. Having admitted the evidence of the defendant’s expert, Dr Molyneux, the judge failed to evaluate it on its merits.
  4. The judge wrongly performed a “balancing” between the rival opinions of the neuroradiology experts.
  5. The judge erred in holding that Dr Molyneux had an interest in the outcome of the case that was sufficient of itself to dismiss his expert opinion when set against that of Dr Butler.

Grounds 1 and 2 and 3 to 5 were grouped together for the appeal.

Irwin LJ gave very short shrift to the appeal under Grounds 1 and 2, that the Judge had misstated the Bolam test, “roundly” rejecting them and observing that there “was no confusion or misdirection”.

With respect to Grounds 3 to 5, the defence submitted that the judge had explicitly recognised Dr Molyneux’s experience and expertise and his concern at the witness’s lack of independence had not caused him to exclude the evidence; if the evidence was to be admitted then, because of Dr Molyneux’s admitted expertise, his evidence must necessarily be accepted as establishing that a responsible body of neuroradiologists would not have referred the patient for further investigation. That was all the more so because the judge observed that he saw the “force” of Dr Molyneux’s opinions, and had not “found it easy to resolve the conflict” between the experts. In those circumstances, the judge could not resolve the matter unless, on close analysis, he found the views of Dr Molyneux to be unreasonable.

The claimant asserted in response that the Judge was fully entitled to place much less weight on the evidence of Dr Molyneux: he had found him to lack the necessary independence and a lack of independence and impartiality in an expert can properly go to admissibility or to weight.

Irwin LJ considered that “the witness had so compromised his approach that the decision to admit his evidence was finely balanced, and that the weight to be accorded to his views must be considerably diminished. In my view he was fully entitled to take that view. Indeed, had he decided to exclude Dr Molyneux’s evidence entirely, it would in my view have been a proper decision. Our adversarial system depends heavily on the independence of expert witnesses, on the primacy of their duty to the Court over any other loyalty or obligation, and on the rigour with which experts make known any associations or loyalties which might give rise to a conflict. Dr Molyneux failed to do so here, despite an express direction to that effect. Indeed, the omission of mention of papers co-authored with Dr Barker points in the other direction.

Furthermore, an issue had arisen regarding the defendant’s neurosurgical expert evidence from Mr Byrne (who was not called at trial), whose report had commented on research by the ISUIA (International Study of Unruptured Intracranial Aneurysms) investigators that had been highly criticised by peers, with Dr Molyneux having been a committee member of the ISUIA at the time of the research. Dr Molyneux knew the study had been inaccurately described by Mr Byrne in his report, such that it “was seriously deficient and misleading”, but did nothing about it. Irwin LJ said, “In circumstances such as those arising here, the scrupulous expert in Dr Molyneux’s position should be pointing out the problem to the legal team well ahead of trial. No doubt that will usually be done in privileged communication. In many instances, a Court will be cautious in drawing inferences for that reason. However, on the facts of this case, the judge found that Dr Molyneux “did nothing” .

Irwin LJ then observed that Dr Molyneux had not explained convincingly the fact that the aneurysm that ruptured in 2011 appeared to have been in the same place as the one on the scan in 1999, giving some latitude for the fact that the imaging in 1999 was of inferior resolution and quality. The judge had preferred Dr Butler’s evidence on this point and had been fully entitled to do so. The appeal court felt that the claimant had “succeeded in establishing Bolam negligence in the conventional way. This was not one of those “rare cases” where a claimant was driven to show that established medical practice was unreasonable. The judge had a considerable body of evidence, firmly expressed by those with proper expertise, to support both the presence of an aneurysm in 1999, and the proposition that any responsible properly qualified neuroradiologist should and would have referred the respondent for further investigation on the basis of the 1999 MRI scan” (Bolitho v City and Hackney HA [1998] AC 232 not applied).

Irwin LJ was satisfied that the case turned on the facts, the Judge had been fully entitled to reject Dr Molyneux’s evidence, and the appeal was dismissed.

As I highlighted in 2015, legal teams on both sides should explore with their expert(s) early on any connection and potential conflict, and take the necessary steps to address the issue, including full, frank and early disclosure should they continue to retain their expert in spite of a potential conflict. The appeal court judgment is a salient reminder of the importance of the independence of expert witnesses to the legal process