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.

We have just published our Guidance for experts on acting for litigants in person. While our general advice to members is not to act for unrepresented parties, there are circumstances in which experts may choose to act for a litigant in person or find that their previously represented party has become a litigant in person.

The judgment dealt with the defendant's application for reverse summary judgment or to strike out the claimant's claim and the claimant's application to strike out the defendant's application and for a stay of related proceedings. The claimant attempted to submit a non-compliant report as 'independent expert evidence' to support his application without obtaining permission to do so.

Cam Askan v HM Land Registry [2026] EWHC 1352 (Ch)

This month on the Expert Matters Podcast, we discuss acting for litigants in person. The accessibility of tools like generative AI is making litigation more accessible to unrepresented parties and it is increasingly likely that experts will be approached by litigant in person. We provide some advice for experts approached by a litigant in person and discuss how an expert should deal with the  situation where their previously represented party becomes a litigant in person. 

The trial dealt with liability issues relating to the alleged use of prohibited defeat devices. That is, devices which reduce the effectiveness of a vehicle’s emission control system for which there is no excuse or applicable exception. The judge criticised three of the expert witnesses for not complying with their duties under Part 35, and praised others.

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 Claimant alleged that the Defendant was in breach of the agreement between the parties for the supply of single alpha chain collagen. The judge was critical of the Claimant’s expert witnesses, in particular noting that he would have had to direct further accounting expert evidence be produced, if the evidence had been required.

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.