Laura Langley, 38, was alleged to have killed her seven-week-old daughter Edith who collapsed at the family home in Blackpool, Lancashire, in the early hours of 20 November 2020. The Judge found that the expert evidence in the case of Professor G, of Professor N and of Professor D each at times fell below the high standard expected of expert witnesses giving evidence before the family court in this jurisdiction. This judgment illustrates a number of important lessons for expert witnesses. The criticisms go well beyond a disagreement between experts—they concern the duties of an expert to the court. An expert who appears to defend a predetermined hypothesis rather than follow the evidence risks losing credibility entirely, regardless of their qualifications or experience. This judgment illustrates that methodological rigour, transparency, and impartiality are essential to persuasive expert testimony.

The applicant, who required leases over mineral rights, could not agree with the owners of those rights on compensation and valuation issues. The expert witnesses for both parties had previously acted as expert advisors to their clients. However, while one expert witness understood that their role was not to advocate for a particular party or outcome but to assist the court, the other expert was unable to disassociate their longstanding role as an expert advisor from their duties to the court.

The proceedings related to a petition asserting unfair prejudicial conduct of the affairs of a company. The expert witness who provided valuation evidence, wrote to the court three months after the trial expressing concerns about his own valuation report.

The Claimants, who were trustees of an angling association which has fishing rights on the River Tees, asserted that the Defendant had interfered with their property rights. The Judge was disappointed that the hydrology experts had inspected the river when it was in very different conditions of water flow. The expert hydrology evidence was also limited to water flow, with no expert evidence available to the Judge on the impact on fish or fishing. One of the experts had also failed to comply with CPR Part 35.

The Claimant brought a claim in negligence against the Defendant, a dental practitioner, about the Defendant’s alleged failure to provide her with adequate advice about the risks and benefits of the treatment options available to her. The Claimant’s expert lacked understanding of the Bolam test, had not considered the dental notes, and was forced to make significant concessions in the joint report.

The operator of the Nord Stream pipeline was suing insurance companies for damages caused to the pipelines by explosions which rendered them inoperable. The Defendant insurance companies asserted that the claim for damage was excluded under the policies. Judge found the evidence of one of the geopolitical experts unsatisfactory because he appeared at times to be seeking to support the Claimant’s case by advancing arguments that flew in the face of common sense and the inferences to be drawn from the known facts.

In her judgment on X and Y (Care Proceedings: Fact Finding: Death of a Child), the Judge was highly critical of the evidence and conduct during proceedings of one of the expert witnesses, a consultant neurosurgeon, Mr M. This judgment, which should be read alongside the earlier judgment, dealt with whether Mr M should be named within that published judgment.

This year’s Annual Conference discussed AI, independence, credibility, transparency and the changing expectations on expert witnesses.

This month on the Expert Matters Podcast, we take a look at the EWI Annual Conference which was held on 19 June. The Conference got off to a great start with a keynote speech on AI & the Expert Witness by Sir Geoffrey Vos, the Master of the Rolls, and carried on with great speakers and panels. Join us on a trip down memory lane as we relive our key highlights from the event. 

This was a fact finding hearing into the death of a young child. The Judge found that the neurologist expert witness failed to discharge his duties as an expert witness to the family court.