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Baby shaking expert case highlights the problems court experts face

The latest ‘baby shaking’ case again flags up the difficulties courts face when hearing expert evidence and experts encounter when giving it.

The High Court has overturned a General Medical Council decision to strike off Dr Waney Squier, a medical expert witness. The GMC found that she was evasive and deliberately misled the court. Mr Justice Mitting, however, found that the determination of the panel was ‘in many significant respects flawed’, reinstating her practising licence but barring her from giving evidence as an expert witness for three years.

Dr Squier is an experienced consultant paediatric neuropathologist at the Oxford University John Radcliffe Hospitals. Since the late 1980s she has developed a medico-legal practice providing reports as an expert neuropathologist and giving evidence in the civil, family and criminal courts. A significant part of her medico-legal practice concerned cases of babies who had died because of suspected non-accident head injury. From around 2002, Dr Squier doubted the majority view as to the indicative signs of such injuries. As a result of the evidence that she gave in court, a Medical Practitioners’ Tribunal determined on 17 March 2016 that her fitness to practice was impaired.

Limiting expert witnesses to their areas of expertise

In one of the charges against Dr Squier, it was alleged that she had presented opinion evidence outside her field of expertise by commenting on biomechanics and ophthalmology. She had referred to research papers which commented on the level of force required to cause injuries, and strongly recommended that the opinion of an expert in biomechanics be sought. She also referred to biomechanics in her oral evidence. The High Court held that the MPT’s conclusion as to her evidence was mistaken and unfair. Nevertheless, expert witnesses should ensure that their evidence falls within their area of expertise and made it clear if they are being pushed to answer questions that come outside it.

Using others’ research papers to support expert evidence: the rules

Sometimes an expert witness will cite a research paper as being in support of their conclusion without qualification. Mitting J noted that ‘Baldly stating, without qualification, that a research paper is a proper foundation for the proposition that the expert is seeking to advance is justified if that is the conclusion of the research paper; but if it is not, it should not be cited, without qualification, as supportive’. He held that Dr Squier often cited a research paper not for its conclusion, which did not support her opinion, ‘but for some nugget’ within it which might do. This was not fulfilling her duty as an expert witness.

He cited Re: AB (Child abuse: expert witness) [1995] 1FLR 181, where Wall J observed that when there was a genuine disagreement on a scientific or medical issue or where it was necessary for one party to advance a particular hypothesis, an expert is under what was termed a heavy duty:

“…the expert who advances such a hypothesis owes a very heavy duty to explain to the court that what he is advancing is a hypothesis, that it is controversial (if it is) and to place before the court all the material which contradicts the hypothesis. Secondly, he must make all his material available to the other experts in the case.”

It is not unusual to see expert witnesses advance confident assertions in often deeply conflicted areas of debate without commenting on the other points of view. PD 35, paragraph 3.2(6) makes it clear that:


(6) where there is a range of opinion on the matters dealt with in the report –

        (a) summarise the range of opinions; and

        (b) give reasons for the expert's own opinion


There was, however, no justification for the MPT’s decision that Dr Squier had been dishonest in cherry-picking research paper: her views were genuinely held.

Acknowledging the pressures on expert witnesses during cross examination

In one of the court cases that Dr Squier gave evidence, it was alleged that she had mis-stated a particular research paper during lengthy cross examination. Auld LJ in Meadow v General Medical Council [2007] QB 462 noted at [205] that there ‘should be an appreciation of the isolation of an expert witness, however seasoned in that role in the alien confines of the witness box in an adversarial contest over which the judge and the lawyers hold the sway’.

At [206-7], he went on to remark on the stresses and strains that arise in litigation: ‘In that, sometimes, fevered process, mistakes can be made, ill-considered assertions volunteered or analogies drawn by the most seasoned court performers, whatever their role.’ Experts should be careful when answering questions, but advocates should also be fair when putting them. At [506], he went on to warn that ‘It is incumbent on the legal representatives on the other side not to encourage, in the form of cross-examination or otherwise, an expert to give opinion evidence which is irrelevant to those issues and/or outside his expertise, and, therefore, inadmissible.’

Expert witnesses: great influence brings great responsibility.

Expert witnesses fulfil an important job for the court, giving evidence in matters that are frequently well outside the experience of the court. It is often difficult for a tribunal or court to choose between two competing views, especially as it may have no clear basis upon which to say which one is correct. In these circumstances, it is especially important that an expert satisfies their obligation to the court to ensure that it is not misled, even inadvertently.

David Sawtell / 7th Nov 2016


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