"A poor quality expert witness can cause serious damage...."

  • Published: February 26, 2021
  • Author: Sarah Sellars, Consultant, Inspire MediLaw

We were honoured to have surgeon David Sellu address our annual Expert Witness Conference in Oxford in December 2020. 

Mr Sellu talked about the events leading up to his conviction and imprisonment for gross negligent manslaughter following the death of a patient, and his successful appeal in 2016.  Mr Sellu was comprehensively cleared of all allegations by the Medical Practitioners Tribunal Service (MPTS) in 2018, leaving him free to return to practice once again.

This experienced, well-respected surgeon should have been able to trust that the legal processes to which he was subjected were fair and faultless. The family of the patient who died were entitled to expect full and proper investigations into the death of their loved one to take place.

Why the role of the expert witness is so important

Mr Sellu shared his experience to encourage medical experts to understand why their role is so important. He explained that their testimony has serious implications. The role of the expert should be taken seriously, and medical professionals should undergo medico-legal training before first accepting instructions to provide an expert opinion. For this reason, Mr Sellu was involved in developing The Surgeon as an Expert Witness guidance, published by the Royal College of Surgeons (England) in 2019.

Understanding your legal obligations as an expert witness

The expert witness plays a key role in legal proceedings, be it coronial, criminal, or civil. Experts should know and understand the different processes of these Courts, and the possible outcomes of a case. For example, while a Coroner will carry out an investigation into a death; the Civil Court will hear a claim for compensation; and criminal proceedings could result in a conviction and, potentially, a prison sentence for the defendant. In each Court, different legal tests are applied and the medico-legal expert should be clear on what is expected of them in this regard.

Mr Sellu warns that cases such as his make the medical profession nervous. People become frightened by what might happen, and begin to practise defensively. He mentioned the number of doctors who take their own lives due to professional pressures, and highlighted the huge emotional burden on a doctor who feels they have let their patient down.  

How might medical professionals as expert witnesses contribute to justice?

Anyone can put themselves forward as an expert witness, regardless of their experience. Mr Sellu advocates a programme of training, accreditation and regulation for medico-legal experts. This would ensure that individuals not only grasp the importance of their duty to the Court, but understand how to carry it out.  

The role of the expert is to set out the realistic, reasonable boundaries of what should have happened and what would be expected of the medical professional on a case. Expert witnesses should only comment on areas within their expertise, and should ensure that they express their opinion in plain English.  

Mr Sellu told delegates that, when his conviction was overturned, there was criticism of the experts and their testimony in his initial trial. The experts used terms that were too complex for a lay jury, and probably also for the judge. The experts explained their views badly, and commented on issues that were outside their area of expertise.  

With Inspire MediLaw's expert witness training, we emphasise the importance of sticking to your area of expertise, both in terms of giving evidence in Court and in report writing.  

Expert witnesses are critical to delivering justice and it is right that they should be well trained, and supported to carry out their duty to the Court to the highest standard.

Paul Sankey, Partner and experienced solicitor in medical negligence at Enable Law, says:

"David Sellu's story should bring home to experts the importance of their role in Court proceedings. 

The Courts rely on them for guidance and will only be able to do justice if experts fulfil their duties. In civil cases, this is a matter of ensuring the right people – those who have suffered harm from negligent care – are able to receive damages and others do not. In criminal cases, someone's liberty and livelihood may be at stake. 

David Sellu lost both and it was not until after he had served a prison sentence that his conviction was quashed. It was quashed because the judge misdirected the jury but also because the experts gave inadequate evidence, evidence which was criticised by the Court of Appeal."

The law, the medicine and the expert witness

Watch David Sellu talk about his case and the importance of medical expert witnesses in our recorded webinar: The law, the medicine and the expert witness.

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