A View from the Tribunal, Counsel and Experts
Monday 9 November 2026 / 9am UK / 5pm HK
Keating Chambers International Webinar Series
The expert supplies knowledge the tribunal lacks; the tribunal keeps the decision (Kennedy [49]).
The expert is never an advocate, in London in 1993 or Hong Kong today.
“An expert witness in the High Court should never assume the role of an advocate.”
Kennedy v Cordia [52]
“An expert witness is not an advocate for a party.”
RHC App D para 4
Four tests (Kennedy [44]): helpful, qualified, impartial, and a reliable body of knowledge.
The weight lies in the reasons, not the conclusion (Kennedy [48]; Griffiths [38]).
The Court of Final Appeal says the same (Nina Kung [20]).
No rules of evidence bind an arbitral tribunal (s.47(3)). The question is usually weight.
“If the reasons stand up the opinion does, if not, not.”
Griffiths v TUI [38]
“The acceptability of an expert's opinion depends very much on how sound and convincing the reasons for his opinion are.”
Nina Kung v Wang Din Shin [20]
What do you want from your expert?
What do you not want?
Four seats: the tribunal, counsel and solicitors, the client, the expert.
The duty to the client and the duty to the tribunal do not conflict.
“Thus there is no conflict between the duty that the expert owes to his client and the duty that he owes to the court.”
Jones v Kaney [49]
How Hong Kong arbitration handles expert evidence.
Simon Hughes KCKeating Chambers
Fairness means a reasonable opportunity, not the Model Law's full one (s.46(3)(b)).
Procedure must suit the case and avoid unnecessary delay or expense (s.46(3)(c)).
No rules of evidence bind the tribunal. It decides the weight (s.47(3)).
Any expert report the tribunal may rely on goes to the parties (s.52).
“to act fairly and impartially as between the parties, giving them a reasonable opportunity to present their cases and to deal with the cases of their opponents”
Cap 609 s.46(3)(b)
IBA Rules and Protocol apply only if adopted. One example: P1 v D [3.37].
| Topic | HKIAC 2024 | IBA Rules 2020 | CIArb Protocol |
|---|---|---|---|
| Party reports | No article; art 22 powers | Art 5.2: instructions, independence, methods | Art 4.4: instructions, fees; art 8 declaration |
| Experts' meeting | None | Art 5.4: meet; record agreement, reasons | Art 6: meet before writing |
| Tribunal expert | Art 25: terms of reference; report to parties; art 11 standard | Art 6 | Not covered |
| At the hearing | Art 22.5: manner of examination | Art 8.4(f) conferencing; 8.4(g) tribunal questions | Art 7.3: preliminary meetings |
“the experts in each subject are to meet on a without prejudice basis to agree a common opinion on the questions within their subject.”
PD 6.1 para 15(6)
The parties must be able to answer a tribunal expert's report (Paklito; Hebei [102]).
Object at once. A party cannot keep the point up its sleeve (Hebei [75]).
Managing expert evidence is case management; the court rarely interferes (Grand Pacific [68], [105]).
Arbitrators may prefer one expert, or take parts of each (CS v HKR [34]).
“A party who has had a reasonable opportunity to present its case would rarely be able to establish that he has been denied due process.”
Grand Pacific (CA) [105]
“an arbitrator is entitled to accept the valuation of one expert over another's, and doing so is neither "plainly wrong" nor "open to serious doubt".”
CS v HKR [34]
What the expert needs, and what gets in the way.
Mike AllenSecretariat
Instructions and an issues list: how clear, and how early?
All of them, including the ones that hurt? (Kennedy [57]; ICI v MMT [237])
Enough time? 44% of experts say yes, against 77% of arbitrators (CIArb 2026).
Survey figures are perceptions, not measurements (CIArb 2026, 419 responses).
“That should include not only material which supports their client's case but also material, of which they are aware, that points in the other direction”
Kennedy v Cordia [57]
Arbitrators: 66% say often. Experts: 73% say never or not often. Who is right?
What does it look like, and how do you refuse the client who pays?
You can no longer support the case. When and how do you say so?
Perceptions, not measurements (CIArb 2026).
“a divergence that represents one of the starkest role-based splits in the entire data set.”
CIArb 2026 report para 2.1.6
“If at any time the expert can no longer support the case of the person who instructed him, it is his duty to say so.”
Guntrip v Cheney [17]
“It takes two to tango.”
Chinachem v Chan Chun Chuen [490]
“Counsel shall have no involvement in the drafting, negotiation or substantive content of any joint expert witness report.”
CIArb 2026 report para 6.1.6
Choosing and paying for experts.
Ben BuryGammon Construction Limited
71% favour appointing before the arbitration starts. When does a contractor first call one?
Counsel blame cost (53%). Experts say their role is misunderstood (42%). Which is it?
Shadow expert, testifying expert, or both? A shadow expert's communications stay privileged (ICC 2021).
Conflict checks at appointment: what should the retainer say? (Toth [112])
“71% of all respondents favouring appointment during the pre-arbitration stage.”
CIArb 2026 report para 2.1.5
“engaging expert witnesses only at the evidentiary hearing stage is inadequate.”
CIArb 2026 report para 1.1.4
Over-instructed often or very often: arbitrators 66%, external counsel 60%, in-house counsel 100%.
Never or not often: 73% of experts (CIArb 2026, paras 5.1.3 to 5.1.5).
These are perceptions, not measurements, and the in-house sample was small (para 1.4.3).
A question: does the client see its own lawyers steering the expert?
“In-house counsel reported the highest perceived incidence of overinstruction”
CIArb 2026 report para 5.1.4
From instructions to cross-examination.
Peter BrogdenKeating Chambers
The report describes the instructions, and under the CIArb Protocol they are not privileged.
Give the expert everything, including what hurts (Kennedy [57]).
State your assumptions; let the expert decline or reformulate them (CIArb 2026 para 5.1.11).
Put the reasons in the report, not only the conclusions (Griffiths [37]).
“a description of the instructions pursuant to which he or she is providing his or her opinions and conclusions”
IBA Rules 2020 art 5.2(b)
Counsel do not negotiate, draft or revise it, directly or through their expert.
Material misunderstanding? Raise it openly with the other side, never privately (BDW [18]).
“The legal advisers must not engage in negotiating, drafting, or revising the experts' joint statement either directly or through seeking to influence their expert as to the contents of the statement.”
TCC Guide 2026 para 14.6.3
“And it is not proper for lawyers to give such instructions on behalf of his clients.”
Chinachem v Chan Chun Chuen [490]
In court, the experts' agreement binds the parties only if they agree (CPR 35.12(5)).
The CPR do not apply in arbitration. There, the question is weight (s.47(3)).
Your expert's change of view does not bind you. A new expert is rare.
Agreed findings will likely stand (IBA Commentary). Revising properly is a duty (Lendlease [69]).
“It is likely that it will be a rare case in which such good reason can be shown.”
Stallwood v David [21]
“if an expert changes his mind about the merits of a claim, the sooner he says so the better.”
Guntrip v Cheney [21]
“That rule extends to both witnesses as to fact and expert witnesses.”
Griffiths v TUI [70]
“The proper course is for each opposing expert to start from a position that is objective and defensible.”
Cabo v MGA [49]
Independence, conflicts, failures of duty, and experts' use of AI.
Mercy MilgoKeating Chambers
Secretariat: an expert group was held to its retainer's express no-conflict term [69]-[81].
The court did not hold that experts are fiduciaries [104].
Disclose any conflict not obviously immaterial; the court, not the parties, decides (Toth [112]).
Hong Kong: an expert's links with a party may cost weight (Redland Precast [31]).
“the relationship between the expert and his client is essentially contractual.”
Secretariat v A Company [105]
“But a conflict of interest is a matter of degree.”
Secretariat v A Company [98]
In Hong Kong the usual answer is weight, not exclusion (Harvest Treasure [22]; s.47(3)).
| Case | What went wrong | Result |
|---|---|---|
| ICI v MMT (TCC 2018) | Expert chose the contract reading; took sides on the facts [184], [237] | The party's four experts lacked independence |
| Dana v Freudenberg (TCC 2021) | Unrecorded client contact; site visits without the other side [83] | Permission refused for all three experts, day 7 |
| Glover (TCC 2024); Marples (Ch 2025) | Joint statement edited by solicitors; rewritten by the client | Permission revoked; refused |
| Tata v DBS (TCC 2024) | Expert advanced a new case over a different period [479] | Outside the expert's role |
Courts elsewhere now ask experts how they used AI. Hong Kong has no rule.
| Where | Instrument | Rule for experts |
|---|---|---|
| Ireland | High Court PD HC 142, from 1 September 2026 | AI declaration at the start of every expert report |
| New South Wales | Supreme Court Practice Note SC Gen 23 (2025) | Court's leave before generative AI drafts any part of a report |
| RICS members worldwide | Surveyors acting as expert witnesses, 5th edn, from 30 November 2026, after this webinar | AI-generated work must be identified |
| Arbitration | CIArb AI Guideline (2025), para 7.3 | Tribunals may impose AI disclosure duties on party experts |
| England and Wales | Civil Justice Council interim report, February 2026 | Proposal only: explain non-administrative AI use; name the tools |
We found no English or Hong Kong judgment criticising an expert's use of AI.
“But when attorneys and experts abdicate their independent judgment and critical thinking skills in favor of ready-made, AI-generated answers, the quality of our legal profession and the Court's decisional process suffer.”
Kohls v Ellison p.9
“We do not consider there to have been any proper foundation for such a serious allegation.”
LR (Albania) [157]
Before the hearing: what do you want from your expert, and what not?
When to appoint, and who pays for the early work?
Should counsel ever see a draft joint statement?
TribunalCounselClientExpert
How should a tribunal test expert evidence, and what should it require about AI?
Cross-examination or conferencing for delay and quantum experts?
An AI declaration like Ireland's: should Hong Kong tribunals require one?
TribunalCounselClientExpert
What would you like to put to the panel?
Type your question in the Q&A box at any time.
The chair puts it to the panellist best placed to answer.
The slides, the authorities and the checklist, with the law as at November 2026.
experts.brogden.io