01 September 2026 Sean Mosby 2 Case Updates Cleveland Potash Limited v The Honourable Mrs Ferelith Drummond & Ors [2026] EWHC 1182 (Ch) by Sean Mosby Summary 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. Learning points If you have been acting as an expert advisor and are then subsequently asked to act as an expert witness in the proceedings dealing with these matters, consider carefully whether you can fulfil your duties. If you have any doubts about your ability to do, you should refuse the instructions. Carefully consider the implications for your opinion of any new factors or information that have come to light after you have submitted your report. You should either change your opinion, explaining why you have done so, or provide an explanation as to why the new evidence does not impact your opinion. Consider listening to the Expert Advisor vs Expert Witness | Expert Matters Podcast, where we consider these issues in more detail. To continue reading you must be an EWI member, become a member and access exclusive content. Already a member? Login More links Link to the Judgment Share Print Tags 07. Receiving Instructions16. Criticism and Complaints08. Working with Instructing Parties15. Giving Oral EvidenceExpert Advisor Related articles Expert Report or MG11 form? Handling future work arising from an existing instruction through a third-party you no longer have a contractual relationship with Lorimer-Wing v Hashmi [2026] EWHC 1843 (Ch) Dermot Speight & Ors (as trustees of the Thornaby Angling Association) v Robert James Pickersgill [2026] EWCC 48 EWI Guidance on Acting for Litigants in Person Switch article A Day in the Life of an Occupational Therapy Expert Witness Previous Article Comments are only visible to subscribers.