What this guide covers
Expert evidence is decisive in UAE commercial and construction arbitration. Quantum claims, delay analysis, valuation disputes, and accounting matters all require expert testimony. Understanding how to structure, manage, and present expert evidence can be the difference between full recovery and a substantially reduced award.
Types of expert evidence in UAE arbitration
Quantum experts (also called damages experts): Assess and quantify the claimant's financial loss. For construction disputes: unpaid contract sums, variations, prolongation costs, loss of profit. For commercial disputes: lost profits, wasted costs, business valuation. Quantum experts must work from the factual record — their opinions are no stronger than the factual assumptions underlying them.
Delay analysis experts (scheduling experts): Address time-related claims in construction disputes — analyse the programme, assess causes of delay and disruption, determine critical path impact, and quantify concurrent delay. Delay analysis methodology (impacted as-planned, collapsed as-built, time impact analysis, windows analysis) is contested terrain — methodology choice can significantly affect outcome.
Valuation experts: Value assets, businesses, IP, or shares as of a specific date. Used in M&A disputes (breach of representation in share purchase agreement), shareholder disputes (fair value of minority shares), and lease disputes (market rent assessment).
Technical/engineering experts: Address causation and defect issues — whether a defect existed, its cause, and remediation cost. Structural engineers, mechanical engineers, IT system experts.
Legal experts: In international arbitration, foreign law is a matter of expert evidence, not judicial notice. UAE law experts required in SIAC or ICC arbitrations applying UAE law; English law experts required in DIAC or arbitrateAD arbitrations applying English law.
IBA Rules framework for expert evidence
IBA Rules Art 5 governs party-appointed expert evidence. Key requirements: (i) the expert report must include the expert's qualifications, instructions (or a description of the factual assumptions), opinions, and a statement of independence; (ii) the expert must confirm the report accurately represents their professional opinion; (iii) the expert must appear for cross-examination unless excused. Art 6 governs tribunal-appointed experts — the tribunal may appoint its own expert on any issue, giving the parties an opportunity to comment on the expert's terms of reference and report.
The independence statement is critical: under Art 5(2)(c), the expert must confirm they are independent of the parties and their representatives. An expert who cannot honestly confirm independence — because they receive significant instructions from that party regularly — creates a credibility problem. Select experts who can genuinely confirm independence.
Concurrent expert evidence (hot-tubbing)
Concurrent expert evidence (hot-tubbing) involves the tribunal examining both parties' experts simultaneously on the same issues, allowing the experts to respond to each other in real time. Benefits: (i) directly exposes the actual disagreements between experts — tribunal can see exactly where and why the experts differ; (ii) saves significant hearing time compared to sequential expert examination; (iii) experts are less partisan and more truthful when their counterpart can immediately respond to overstatements; (iv) it produces a clearer record for the award.
Best practice: propose hot-tubbing at the first CMC for all expert evidence in technical disputes. Prepare a joint expert protocol with the opposing party — agree in advance the list of issues for concurrent examination and a timetable for the experts to produce a joint statement identifying agreed and disagreed issues (the "Scott Schedule" equivalent for experts).
Practical checklist
- Expert selection: instruct the expert before the claim is filed — waiting until the statement of claim is served gives inadequate time for a proper expert report
- Instructions: provide the expert with complete factual instructions, all relevant documents, and a clear description of their role — do not cherry-pick documents
- Independence: check the expert has no material relationship with either party or its counsel that would compromise independence
- Joint expert meeting: propose at CMC that the experts meet without counsel to identify agreed and disagreed issues — this narrows the expert dispute and saves hearing time
- Concurrent evidence: propose hot-tubbing at CMC for quantum and delay experts
- Tribunal-appointed expert: in cases where both parties' experts are significantly divergent, proactively suggest tribunal-appointed expert under IBA Rules Art 6 — shows confidence in your position
What we'd typically advise
The most important advice on expert evidence: brief your expert early, brief them completely, and let them form their own view. An expert who has been briefed selectively or coached to reach a predetermined conclusion will be exposed in cross-examination. A credible expert who reached their view independently and can withstand robust questioning is worth far more than a compliant expert who says what your counsel wants but crumbles under pressure.
Frequently asked questions
Can legal counsel draft the expert report?
No — the expert report must represent the expert's independent professional opinion. Counsel may assist in structuring the report and identifying the questions to be addressed, but the substance must come from the expert. An expert who openly defers to counsel's views loses all credibility. The expert must be able to confirm in cross-examination that the opinions expressed are entirely their own.
What happens if the tribunal rejects both parties' expert evidence?
The tribunal may exercise its power under IBA Rules Art 6 to appoint its own expert, whose opinion the parties can comment on. Alternatively, the tribunal may draw inferences from the documentary evidence available or find that the claimant has not met its burden of proof on quantum. This is the worst outcome for the claimant — quantum not proven. Avoid it by ensuring your expert opinion is well-founded and properly supported.
Can a party change its expert after the first report is submitted?
Only with tribunal permission and good cause. The change of expert at a late stage is viewed with suspicion — it suggests the original expert reached conclusions unhelpful to the party. Legitimate grounds for change: expert death, serious illness, or genuine conflict identified after appointment. Tactical expert changes to get a better result are generally refused.
Is a UAE-qualified lawyer always needed as a UAE law expert in foreign-seated arbitration?
The expert must have genuine expertise in UAE law — typically demonstrated by UAE law qualifications, years of UAE law practice, or significant academic work on UAE law. A UAE-qualified lawyer with limited practice experience is not necessarily a better UAE law expert than an experienced English lawyer with 15 years of UAE law practice. What matters is depth of genuine knowledge, not formal qualification alone.
What is a Redfern Schedule and is it used for expert evidence?
A Redfern Schedule is typically used for document production requests (each request, the response, and the outcome in columns). For expert evidence, the equivalent is a Scott Schedule or issues matrix — a table listing each expert issue, each party's position, and eventually the tribunal's determination. Scott Schedules are very useful for quantified items (variation claims, cost items) where there are many individual disputed values.
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Published 20 May 2026. General information only — not legal advice. Contact us for matter-specific advice.