A Devastating Case

A Family Court judgment published in November 2025 offers a stark reminder of what the court expects from medical expert witnesses Re X and Y.  The case, Re X and Y, arose from the death of a two year old girl, P, following a catastrophic head injury sustained at home in November 2023. Her mother and father each pleaded guilty to child cruelty. The mother was also charged with murder. Mrs Justice Knowles conducted a lengthy fact finding hearing to determine how P’s injuries were caused.

A Single Dissenting Expert

Eight consultant experts were instructed across the family and criminal proceedings, covering neurosurgery, neuroradiology, ophthalmology, pathology and paediatric intensive care. Seven reached a broadly consistent view. P had suffered a severe traumatic head injury caused by shaking, with or without impact.

One expert stood apart. Mr Patrick Mitchell, a consultant neurosurgeon instructed on behalf of the mother, argued that P’s collapse could be explained by choking on a biscuit followed by a resuscitative shake. He suggested that P had enlarged spaces around her brain which may have reduced the force needed to cause her injuries.

The Judge’s Criticisms

The judge rejected his evidence. She found that Mr Mitchell had only skimmed the papers and the reports of the other experts. He had drawn conclusions based on speculation rather than verifiable medical sources or clinical experience. He showed an unwillingness to engage with contrary opinion and conceded only once that a question fell outside his own expertise. His written and oral evidence failed to set out where he disagreed with the other experts, why, and what the alternative explanations might be.

The local authority and the children’s guardian invited the court to name Mr Mitchell in a published judgment and to send the judgment to the General Medical Council. Mr Mitchell opposed being named. He argued that criticism of his conduct was better addressed through a GMC process and warned that naming him could deter others from acting as expert witnesses in family proceedings. The judge found no evidence to support either concern.

Lessons for Expert Witnesses

For medico-legal practitioners, the case restates familiar duties in unusually sharp terms.

An expert’s overriding duty is to the court not to the party instructing them. Where the evidence of others differs from your own, that disagreement must be addressed directly, with reasons, in the report and in oral evidence.

Stay within your area of expertise. Where a question falls outside it, say so clearly and defer to the relevant specialist.

Prepare thoroughly for oral evidence. If a question needs further research to answer with confidence, say so and set out the caveats that apply.

If late instruction limits your ability to meet these duties, ask for more time. The court is unlikely to accept time pressure as an excuse for a report that does not show its working.

Where several experts from different disciplines are involved, take a multidisciplinary approach and defer appropriately to others’ fields. Consistency matters too. If you give evidence on the same case in more than one jurisdiction, make sure your evidence is consistent, or be ready to explain clearly why it differs.

The Wider Message

Re X and Y is an unusually severe illustration of these principles, but the principles themselves are not new. What the case adds is a clear demonstration of the consequences when an expert departs from them: rejected evidence and published criticism and a referral that will follow the expert into future instructions.