Legal: Being a competent expert witness

A recent county court case highlighted the risks that expert legal witnesses face if commenting on clinical matters beyond their expertise.

  • Date: 31 January 2022

A RECENT judgment from the county court has highlighted the risks involved when accepting instructions to become an expert witness.

The case (Robinson v (1) An NHS Trust and (2) Dr Mercier [2021]) concerned expert evidence provided by a general dental practitioner – Dr Mercier – in a dental negligence claim against an oral maxillofacial surgeon's employing trust. The case involved a tooth extraction performed under general anaesthetic.

Dr Mercier was instructed by the claimant solicitors and provided a report to the court regarding the standard of care provided by the dental surgeon, but at trial he conceded that he had never worked in a hospital setting, and had no experience of teeth extraction under general anaesthetic since 2000. He also agreed that an expert oral maxillofacial surgeon providing evidence for the defendant was better placed to comment on the case.

The claimant in the negligence case discontinued her claim following evidence at trial and the defendants then applied to the court to recoup their legal costs.

Flagrant disregard

In her judgement awarding a third-party costs order of over £50,000 against Dr Mercier, the recorder criticised the GDP, concluding that he had shown a flagrant disregard for his duties to the court and a lack of understanding of the relevant legal tests.

The recorder further held that “but for Dr Mercier’s report, the claim would not have been brought” and that “a public body has been put to considerable expense”. Nonetheless, she made it clear that the cost order was made solely on the basis that Dr Mercier was not the appropriate expert to opine in the negligence case.

A similar order for wasted costs was made against an expert in the case of Thimmaya v (1) Lancashire NHS Foundation Trust and (2) Firas Jamil [2020]. The expert – Mr Firas Jamil – also failed to exercise his duties to the court, which led to the claimant discontinuing the claim at trial.

In particular, Mr Jamil was unable to articulate the Bolam/Bolitho legal test to be applied in determining breach of duty in a clinical negligence case. He accepted that with hindsight at the time of the trial he was not fit to give expert evidence due to mental health problems and should have ceased his medico-legal work.

Practical advice

In agreeing to act as an expert in legal proceedings, you must always bear in mind that you have an overriding duty to the court, not to your instructing solicitors or any other involved party.

You must also restrict your comments or objective opinion on matters to those areas that fall within your expertise. It is your sole responsibility to make it clear when an issue falls outside of that remit.

The case against Dr Mercier highlights how commenting on issues outside your area of expertise and contemporaneous practice can carry the risk of costly consequences.

Action points

  • Experts considering undertaking medico-legal work must understand their duties to the court and the potential consequences of failing to do so.
  • Only accept instructions within your area of expertise, having regard to both specialty and your contemporaneous practice.
  • Responsibility for medico-legal work cannot be delegated to your instructing solicitor; you must personally ensure you are fulfilling your duty to the court at all times.

Related resources

This page was correct at the time of publication. Any guidance is intended as general guidance for members only. If you are a member and need specific advice relating to your own circumstances, please contact one of our advisers.

Related Content

Medico-legal principles

Raising concerns

Coroner's inquests

Save this article

Save this article to a list of favourite articles which members can access in their account.

Save to library

For registration, or any login issues, please visit our login page.