Tainted Expert Evidence No Answer to Bolam Claim Says Court of Appeal

News | Fri 10th Feb, 2017

Acting for a member of the judiciary, Grahame Aldous QC and Stuart McKechnie have succeeded in upholding a High Court judgment for a claimant in a clinical negligence claim on appeal in the Court of Appeal. Their argument that the evidence relied on by the Defendant doctor was rightly rejected as tainted by a lack of independence and objectivity was upheld by the Court of Appeal on 10th February 2017 in the case of EXP v Barker [2017] EWCA Civ 63 The case raises important questions about impartiality and conflicts of interest for expert witnesses.

On 8th September 2011 the Claimant, a full-time District Judge who was referred to as EXP, suffered a catastrophic aneurysm bleed requiring life saving surgery and resulting in devastating neurological injuries. It was alleged on behalf of the Claimant that the aneurysm had been visible on a MRI brain scan taken on 6th April 1999, but had not been identified and so was not followed-up and treated. The scan had been reported as ‘entirely normal’ by the Defendant, an experienced Consultant Neuroradiologist .

A pleaded defence on causation was abandoned shortly before trial. This left two issues for trial, a) whether the MRI scan in 1999 did indicate the presence of an abnormality which a reasonably competent Neuroradiologist would have identified and reported for further investigation, and b) whether the abnormality, if there, was in fact the aneurysm that eventually ruptured with such catastrophic consequences. Whilst seemingly narrow issues, they sharply divided the medico-legal experts instructed by the parties.

In his defence of the claim, the Defendant relied upon expert evidence from Dr. Andrew Molyneux (an eminent Consultant Neuroradiologist) who concluded that the 1999 MRI scan showed no clear evidence of a cerebral aneurysm. This was in contrast to the expert evidence called on behalf of the Claimant from Dr. Paul Butler (another eminent and experienced Consultant Neuroradiologist) that the scan showed an abnormality that was in fact the aneurysm that ruptured, and which should have been investigated following the 1999 scan.

As a result of cross-examination of the Defendant at trial it was revealed that the Defendant and Dr. Molyneux had a long and extensive connection, involving Dr Molyneux training the Defendant at the Radcliffe Infirmary in Oxford, assisting and inspiring him in his career development, helping him obtain posts in the UK and abroad, writing at least 1 peer reviewed publication together and serving at the same time on the committee of the British Society of Radiologists. It also emerged from detailed cross examination that the Defendant had been responsible for suggesting Dr. Molyneux as a Defence expert. The extent of the relationship between the two specialists was inadvertently disclosed during cross-examination when Dr. Molyneux referred to the Defendant by his first name “Simon”, in what the judge described as an unguarded moment.

Mr Justice Kenneth Parker handed down judgment at the Royal Courts of Justice, London on 7th May 2015 after a 4 day trial on liability and causation that was heard in February 2015. In his written judgment Mr. Justice Kenneth Parker reviewed the authorities in relation to disclosure of potential conflicts of interest by expert witnesses (including the guidance issued by the GMC). He rejected the suggestion that it had been for the Claimant to investigate the defence witnesses before trial and holding that the responsibility for disclosure lay firmly on the defence side he concluded that there had been a very substantial failure:

“to disclose, with adequate particularity, the nature and extent of Dr. Molyneux’s connection with Dr. Barker, so that the Court would have a complete understanding of all matters that could realistically affect Dr. Molyneux’s independence as an expert witness”.

Mr. Justice Kenneth Parker went on to note that he had come very close to ruling Dr. Molyneux’s evidence inadmissible on the grounds that the court could not have confidence in his impartiality and objectivity as an expert witness. The Court of Appeal considered that, had he done so, it would have been a proper decision that he was entitled to make. However, having heard Dr. Molyneux’s expert evidence relating to the key issues at trial, the judge decided that he should admit such evidence, but subject to powerful arguments regarding its weight.

Having considered the respective expert evidence, Mr. Justice Kenneth Parker concluded that he had complete confidence in the objectivity and independence of the Claimant’s experts, Dr. Butler and Mr. Kirkpatrick. He therefore much preferred to accept their opinions than the opinion of Dr. Molyneux, whose independence and objectivity had been very substantially undermined. Accordingly he rejected Dr Molyneaux’s evidence and there was judgment for the Claimant with damages to be assessed.

There was no appeal against the findings of the trial judge that the independence and objectivity of the defence evidence had been undermined, nor the finding that aneurysm that ruptured in 2011 was the same aneurysm that could be seen on the 1999 scan. However the Defendant appealed on the basis that, since the judge had not ruled the tainted expert evidence as inadmissible, he should have considered whether it withstood logical analysis before he could reject it.

The Court of Appeal rejected that submission and agreed that the judge was entitled to reject the tainted evidence and decide the case on the evidence relied on by the Claimant in which he had complete confidence. Having rejected the evidence that there was a responsible body of neuro-radiologists who would have considered the 1999 scan as normal the Claimant succeeded in establishing Bolam negligence in the conventional way and it was not one of the ‘rare cases’ where a Claimant was driven to show that established medical practice was unreasonable.

This case highlights the importance of ensuring that expert witnesses are wholly impartial and that any potential conflict of interest is disclosed at the earliest stage possible. These responsibilities apply not only to expert witnesses, but also to those instructing them and relying on their evidence.