Update: Maximising the Effectiveness of Party-Appointed Expert Witness Evidence in ADR
Ciarb is pleased to announce that the project Maximising the Effectiveness of Party‑Appointed Expert Witness Evidence in Arbitration, first initiated in 2024, has entered the consultation phase following extensive industry engagement.
The project, inspired by themes explored in Sir Robin Knowles CBE’s 2025 Roebuck Lecture, Damages and Remedies – Responsibilities and Reputation, aims to provide practical, globally applicable guidance for counsel, tribunals, and expert witnesses that is grounded in real user experience.
The lecture highlighted two enduring challenges in the use of expert witness evidence in dispute resolution: that responsibility for improving the use of expert witness evidence rests primarily with its users; and that engaging with expert witnesses for the first time at the evidentiary hearing is unacceptably late.
Recognising that expert witness evidence is often decisive in arbitration, the international working group, co‑chaired by Ciarb Deputy President Michael Tonkin C.Arb FCIArb and Pamela McDonald MCIArb, set out to gather global perspectives on how expert witness evidence is prepared, communicated, understood and used.
Following a series of webinars, workshops, Let’s Discuss sessions, and publication of a survey that drew more than 400 responses from expert witnesses, arbitrators, lawyers and in‑house counsel, we have gathered considerable data.
This data has been organised around four themes:
- Communication between expert witnesses, the tribunal, and counsel
- Timetables and the timing of expert witness involvement
- Ensuring the tribunal understands the expert witness evidence
- Hearing and post‑hearing issues
Four regional working groups totalling around 40 members across the Americas, Europe, Africa, the Middle East and the Asia Pacific have produced draft commentary and guidance on these themes. These drafts have been exchanged across regions and consolidated into one text.
Pamela McDonald MCIArb said: “This project reflects our shared commitment to improving how expert evidence is prepared, presented and understood. By engaging with practitioners across disciplines, the project helps ensure that the guidelines we develop are practical, balanced and genuinely enhance the arbitral process.”
Michael Tonkin C.Arb FCIArb said: “I am truly grateful to have had the opportunity to work on this incredibly important project for the benefit of our global community, and to do so with so many experienced and dynamic individuals who have given freely their time and support.
After more than two years of research and debate, we have now entered the consultation period and, once complete, we will be able to share our findings and recommendations. We very much look forward to debating the findings and recommendations of our report with other users and hope that you find our work both interesting and helpful.”
Ciarb extends its sincere thanks to everyone across the global arbitration community who has contributed to this project so far. These insights continue to shape a resource that aims to enhance confidence in expert witness evidence in arbitration, promote earlier and more effective engagement with expert witnesses, and support the fair and efficient resolution of disputes worldwide.
Ciarb plans to publish the report, Maximising the Effectiveness of Party‑Appointed Expert Witness Evidence in Arbitration, in May 2026.
In June 2026, Ciarb will host a global webinar to present the final guidance, discuss practical implications, and launch supporting materials.
