Your DIFC Expert Report Sounds Like Advocacy: What Needs to Change?

A DIFC expert report must assist the court independently, not present the paying client's preferred conclusion as technical fact. Under RDC 31.3 to 31.7, the expert's duty to the court overrides obligations to the person instructing or paying them. If a report ignores adverse material, exceeds the expert's field or reads like a legal submission, address that before relying on it.

The answer is not to remove every sentence that sounds unfavourable. Check the permitted issue, the expert's qualifications, the material supplied and the reasoning connecting facts to conclusions. A properly explained limitation is more useful than a confident answer the expert cannot support under questioning.

What makes a DIFC expert report vulnerable?

Problem	Question for review	Appropriate response to consider
Report repeats the client's argument	Where is the independent technical analysis?	Ask for reasons, method and relevant alternatives
Adverse records are missing	Was the expert given all material facts?	Provide the records and invite independent reconsideration
Conclusion exceeds expertise	Is the topic within the expert's actual field?	Clarify limits and consider appropriate permission
Assumption treated as proven fact	Who supplied it and what changes if it is wrong?	Identify the assumption and test its effect
Report outside the court order	What expert evidence was permitted?	Check scope and seek directions where needed

Start with the court's order, not the expert's invoice. Permission may concern a named expert or a defined field. A broadly worded retainer between the client and consultant does not expand what the court has allowed as evidence.

Create a review note with references to the report paragraphs that concern you. Explain whether the problem is an omitted record, unexplained method, disputed assumption or an opinion outside the permitted subject. A complaint that the expert is not helpful enough gives little useful direction.

The same approach applies when reviewing the opponent's report. Identify the technical weakness rather than simply alleging bias because the other party paid the expert.

The duty is to the court, even when you pay the bill

RDC 31.5 requires expert evidence to be the expert's independent product, uninfluenced by litigation pressure. RDC 31.6 calls for objective and unbiased opinion within the expert's expertise and says the expert should not assume an advocate's role.

Those duties explain why a client cannot require a particular conclusion as the deliverable. You may identify an error, ask that missing material be considered or request a clearer explanation. You should not insist that the report reach a figure or finding simply because the pleaded case depends on it.

RDC 31.7 expressly includes material facts that detract from the expert's opinion. Do not give the expert only the documents that favour the case. If the records are incomplete, explain the gaps and how the selection was made.

For example, a valuation based only on the strongest trading month may need to address other relevant periods and unusual events. An expert assessing a technical failure may need the maintenance history as well as the photograph of the damaged component. These are illustrative questions, not conclusions about a particular method.

Ask the expert to explain how contrary material affects the analysis. The answer may be that it changes nothing, changes the range or prevents a firm conclusion. The important point is that the response comes from the expert's reasoned assessment, not from editing by the litigation team.

Separate the fact witness, lawyer and expert roles

A person who participated in events may provide factual evidence about what they saw or did. An expert assists on a matter requiring their expertise. A lawyer presents legal argument. Putting an account into a document called an expert report does not erase the distinction between those functions.

In Sky News Arabia v Kassab Media, CFI 007/2016, 20 June 2016, paragraphs 11 to 13, the court excluded a statement from the claimant's external lawyer under the practice direction considered there. It retained the possibility of considering opinions as submissions. It admitted the in-house witness's account of personal knowledge.

The 12 July 2017 appeal also excluded recovery of the costs of preparing the rejected statement. The jurisdiction appeal was dismissed, with an applicable-law issue remitted. This was not a general ruling that employees cannot be witnesses or that every lawyer's statement is forbidden.

Use the example for the importance of evidence roles. The current expert duties in this guide come from Part 31, not from treating the historical statement dispute as an expert disqualification code.

For your case, identify which facts require a person with direct knowledge and which questions require specialist opinion. If one person potentially performs more than one role, discuss how the distinction should be presented and whether that person is suitable for the proposed expert task.

Check permission and the precise field before commissioning more work

Under RDC 31.12, expert evidence is restricted to what is reasonably required to resolve the proceedings. RDC 31.13 requires permission before calling an expert or putting the report in evidence. Permission should normally be sought at the case management conference under RDC 31.14.

The application identifies the field and, where practicable, the expert. RDC 31.16 confines permission to the named expert or identified field. A report that expands into another discipline should therefore prompt a scope check rather than simply being added to the trial bundle.

Give the expert the actual order. RDC 31.19 requires the instructing party to serve an order that requires an act by the expert or otherwise affects them. Summarising it orally risks losing an important limitation, deadline or assumption.

Before authorising additional analysis, identify the question it answers and where it falls within the permitted issues. If it is outside them, seek advice about whether further permission is necessary and proportionate. An expensive report can still be unusable if the procedural requirements have not been met.

Also check the exchange sequence and any directions about testing, inspection or meetings. A consultant may be available to write quickly but unavailable for the ordered expert discussion or trial. Availability for the whole assignment matters when selecting the person and planning the work.

Obtaining permission is not the last procedural step. RDC 31.65 provides that a party which fails to produce its expert report may not use it at trial or call the expert orally without permission. Keep proof of the required production with the final report. RDC 31.18 also permits limits on recoverable expert fees and expenses, so commissioning more work does not assure recovery of its full cost from the opponent.

Write instructions that expose assumptions instead of hiding them

The report must state the substance of material instructions under RDC 31.53. RDC 31.55 also requires the material facts and instructions on which opinions are based. An instruction that quietly assumes the disputed conclusion makes the resulting opinion difficult to evaluate.

Separate accepted facts, disputed facts and hypothetical assumptions in the instructions. If the expert is asked to calculate an outcome on two possible factual findings, label both scenarios. The expert should not resolve an issue outside their expertise merely to make a spreadsheet produce one final number.

Use a document index showing what was supplied, when and in which version. If an important document arrives later, identify whether it replaces an earlier version or adds new information. Ask the expert to consider whether it affects any existing conclusion.

These distinctions help the report remain auditable.

RDC 31.54 addresses production and questioning about instructions, with specified safeguards. Do not promise that everything said to a testifying expert is immune from scrutiny, or assume that the opponent can demand every communication without meeting the rule.

Require a method, source material and an honest range

A conclusion should be traceable. Ask what data was used, how it was analysed, why the chosen method fits the question and what uncertainty remains. A report does not become stronger merely because the conclusion is repeated in its introduction, table and summary.

RDC 31.55 requires qualifications, relied-on literature or material, relevant facts and instructions, and identification of facts within the expert's own knowledge. Where testing or measurement has been used, the report identifies who did it, their qualifications and the expert's supervision.

Where a range of opinion exists, the report should summarise the range and explain the expert's own view. It must also address unreasonable or unlikely assumptions and qualifications on the opinion. These requirements are particularly important when a precise-looking figure rests on uncertain inputs.

In a hypothetical loss calculation, check whether the model uses actual records, management estimates or an assumed growth rate. Ask the expert what changes when a disputed input changes. A sensitivity exercise can reveal that the legal dispute is really about one assumption rather than the mathematics.

RDC 31.21 addresses photographs, plans, analyses, measurements and similar material relied on, as well as unpublished sources, to be supplied with the report unless already provided. Keep those materials organised and readable. A broken reference to a spreadsheet tab can prevent another expert from following an otherwise sound calculation.

Do not substitute a decorative chart for the working analysis. The reader should be able to identify the source of the plotted data and the calculation producing it.

What if the expert cannot give a definite opinion?

RDC 31.8 requires the expert to make clear when an issue is outside their expertise or when insufficient information prevents a definite opinion. RDC 31.9 requires an inadequately researched opinion caused by insufficient data to be identified as provisional.

That disclosure is not a drafting defect to be removed. It tells the court and the parties what the report can reliably establish. Ask whether the missing information can be obtained, whether the issue can be narrowed or whether a different specialist is needed.

A provisional view may still help the legal team understand what evidence matters. It should not be promoted into an unconditional court conclusion without the work necessary to support that change. Keep internal preliminary advice distinct from the report proposed as evidence.

If more information would take significant time or cost, obtain an explanation of its likely usefulness. There may be little point in commissioning a test that cannot distinguish between the competing factual possibilities. The expert should identify that limitation before resources are committed.

When the expert changes a material view after reporting, RDC 31.11 requires communication without delay to all parties and, when appropriate, the court through the relevant representatives. Do not retain an old favourable opinion in the bundle while privately working from a different conclusion.

Review the draft without rewriting the expert's opinion

Legal review can identify ambiguity, missing reasons, incorrect document references or matters outside the permitted questions. It should not convert a report into a more favourable opinion by deleting qualifications or inserting conclusions the expert does not hold.

The protocol reproduced in the Schedule to Part 31, paragraph 15.2, distinguishes proper amendments for accuracy, consistency, completeness, relevance and clarity from changes that distort the expert's true opinion. Part 31.2 describes the protocol as practical guidance and notes that not every part applies to DIFC litigation.

Use comments that ask questions rather than dictate answers. Instead of instructing the expert to remove an inconvenient alternative, ask why it is or is not supported by the data. Instead of replacing a range with one figure, ask whether the evidence justifies a central estimate and how it should be qualified.

Keep an intelligible version history. If a document was corrected or a calculation changed, record what prompted the change. That does not mean every draft is automatically producible, but it avoids confusion about which opinion the expert actually adopted and why.

Common mistake. Editing out an adverse assumption or qualification can change the substance of the opinion. Ask the expert to address the issue independently rather than improving the appearance of the result.

Before service, confirm that the expert has read the final text and accepts its reasoning, sources, limitations and statement of truth. Approval of an earlier draft is not approval of later substantive edits.

Use written questions for clarification, not a second pleading

RDC 31.24 permits written questions to another party's expert or a court-appointed expert about the report. Under RDC 31.25, they are normally put once, within 28 days of service and only for clarification, unless the court gives permission or the instructing party agrees.

Questions should identify the passage and the uncertainty. For example, ask which record supplies a stated input, whether an assumption includes a particular event or how an apparent arithmetic inconsistency is resolved. Do not use a long series of accusations as a substitute for focused clarification.

RDC 31.26 addresses oppressive questions and questions outside clarification, including disallowance and an appropriate costs order. The opportunity to question is not an unrestricted right to require the expert to redo the entire case on a new basis.

Answers become part of the report under RDC 31.27. Review them against the original conclusions. If an answer changes an assumption or exposes missing material, decide with counsel whether further directions or a response from your expert are appropriate.

RDC 31.28 permits specified consequences where a party's expert fails to answer a proper question, including restrictions on reliance or recovery of the expert's fees. Those are court powers, not consequences a party should announce as already automatic.

Calendar the question period when the report arrives. Technical review can take time, particularly where spreadsheets or testing records require examination. Waiting until trial preparation may lose the ordinary opportunity for clarification.

Let expert discussions identify genuine agreement

Part 31 contemplates meetings to identify issues and agreement or disagreement between experts. RDC 31.60 leaves procedure to the experts, subject to directions. RDC 31.61 says the parties and lawyers should not restrict their freedom to acknowledge agreement.

Do not instruct an expert to maintain a disagreement merely because conceding the technical point would make the client's argument harder. A properly explained agreement can narrow the dispute and reveal what genuinely requires decision.

RDC 31.63 normally calls for a joint memorandum recording the meeting, agreed issues, disagreements and brief reasons. Read it carefully alongside the reports. An apparent disagreement may concern different assumptions rather than different professional methods.

The content of expert discussions is not referred to at trial unless the parties agree under RDC 31.62. Distinguish that restriction from the joint memorandum intended for the court. Do not assume every informal discussion remark belongs in cross-examination.

Under RDC 31.64, expert agreement does not bind the parties unless they expressly agree to be bound. That does not justify pressuring an expert to withdraw an honestly held agreement. Ask counsel to distinguish the party's legal position from the expert's professional conclusion.

If an expert has changed an opinion, ensure the report record and any necessary notification reflect it. A joint memorandum and an unrevised report should not leave the court guessing which view is current.

A court-appointed expert is not an unanswerable decision-maker

RDC 31.29 permits the court to appoint independent experts on specified issues. The court establishes the terms of reference. This differs from simply treating one party's consultant as if the court had selected them.

RDC 31.32 and 31.33 provide for an independence statement and written objections within seven days of receipt. If there is a concrete concern, identify the relationship or interest and supporting facts promptly. Disagreement with the likely opinion is not the same as an independence concern.

After the report, RDC 31.42 permits a response within 28 days of receipt through a submission or expert report, served on the court, the court-appointed expert and the other parties. The route and any case-specific directions should be checked before responding.

RDC 31.44 allows the court to direct attendance and questioning. RDC 31.45 leaves the weight of the report and conclusions to the court. Appointment does not turn the expert into the judge of the dispute.

Cooperate with proper information and inspection arrangements while raising any genuine objection through the applicable process. Identify what the expert requested, what was supplied and any restriction affecting the work. An incomplete factual record can impair a court-appointed assessment just as it can impair a party's report.

Put the expert evidence into a usable hearing plan

Before trial, check the current report, answers, joint memorandum and source materials as one set. Note any changed opinion and the issue that remains for oral evidence. Do not prepare the hearing from an outdated summary that predates the expert meeting.

RDC 31.48 permits concurrent expert evidence where directed. The experts may give evidence as a panel with questioning managed by the court. Ask what format has actually been ordered and ensure the expert is available and prepared for that format.

Use these records to complete preparation.

1. Confirm permission, field, expert identity and timetable.
2. Supply material records and clearly separated factual assumptions.
3. Review the method, qualifications, limitations and report requirements.
4. Correct errors without dictating conclusions or suppressing adverse material.
5. Complete proper clarification and expert-discussion steps.
6. Prepare the current opinion and source record for the directed hearing format.

Key takeaway. The useful expert is the one whose reasoning can be examined, including its limitations. A report written to secure agreement with the client is answering the wrong task.

Sources checked on 29 September 2026. This is guidance on DIFC evidence procedure, not an opinion on the correct technical method for a particular dispute.

Frequently Asked Questions

Does paying an expert entitle me to choose the conclusion? No. RDC 31.3 to 31.7 require independent assistance to the court, including consideration of adverse material.

Can I file any expert report I commission? No. RDC 31.13 requires permission to put a report in evidence or call the expert. Check the named expert or permitted field and directions.

Should the report disclose material assumptions? Yes. RDC 31.53 and 31.55 address material instructions, facts, assumptions and qualifications on the opinion.

Can lawyers review the expert's draft? Review for accuracy, completeness and clarity should not distort the expert's true opinion. The Schedule to Part 31 addresses that distinction.

How long do I ordinarily have for clarification questions? RDC 31.25 provides 28 days from service and normally one set for clarification, subject to permission or the instructing party's agreement.

Can I stop my expert agreeing with the other expert? The parties and their lawyers should not restrict an expert's freedom to acknowledge agreement under RDC 31.61.

Does expert agreement automatically bind the parties? No. RDC 31.64 requires the parties' express agreement to be bound. The expert's independent professional view remains distinct.

Can a court-appointed report be challenged? Part 31 provides for responses and questioning where directed, and the court decides the report's weight. Observe the applicable timetable and directions.

This article provides general information and does not constitute legal advice. Consult a qualified advocate about expert permission, instructions, disclosure and the evidence needed in your case.

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