How to use this checklist

Work through the phases in order, but start Phases 1, 2, and 5 at the same time: the procedural rules, the witness list, and the expert team all need to be in place before the first written submission. Each item is a task with its governing authority and, where useful, a short practical note. References to "the IBA Rules" are to the IBA Rules on the Taking of Evidence in International Arbitration (2020). Most tribunals are "guided by" rather than bound by them, but treat their requirements as binding unless Procedural Order No. 1 (PO1) says otherwise.

Institutional rules supply the frame: ICC Rules (2021) arts. 25 and 26; LCIA Rules (2020) arts. 19 to 21; UNCITRAL Arbitration Rules (2010, as amended 2013) arts. 27 to 29; ICSID Arbitration Rules (2022) Rules 36 to 40. Check which apply before using this list. The doctrine behind each item is explained in Evidence in International Arbitration: The IBA Rules, Document Production, Witness Statements, and Expert Evidence, and templates for the statements, instructions, and protocols are in the Arbitration Evidence Toolkit: Redfern Schedules, Witness Statement Templates, and Expert Protocols. Document production, which feeds every witness statement and expert report, is covered in Requesting and Resisting Document Production in International Arbitration: A Practical Guide.

U.S. lawyers should keep one contrast in mind throughout. The Federal Rules of Evidence govern proceedings in U.S. courts (Fed. R. Evid. 1101), not arbitrations, and there are no depositions as of right. The witness statement is the direct examination; the hearing is mostly cross-examination; and the tribunal decides admissibility and weight without Daubert gatekeeping.

Phase 1: Secure the witness and expert provisions of PO1

  • Confirm whether the IBA Rules bind or guide. Authority: IBA Rules art. 1; ICC Rules art. 19 and art. 25; UNCITRAL Rules art. 17(1). Note: "guided by" is the common formula; ask the tribunal to say which provisions it will apply strictly.
  • Fix the sequence of written evidence. Witness statements and expert reports with each memorial, or simultaneous exchanges? Reply statements allowed? Authority: IBA Rules arts. 4.4, 4.6, 5.1, 5.3. Note: sequential exchange favors the respondent, which sees the claimant's evidence first; simultaneous exchange often produces reports that talk past each other.
  • Limit reply statements to responsive matters. Authority: IBA Rules art. 4.6 (revised or additional statements respond to matters in the other side's evidence or to new developments). Note: ask for a rule that new matters in reply require leave.
  • Agree the standard for witness preparation. Authority: IBA Rules art. 4.3; LCIA Rules art. 20; IBA Guidelines on Party Representation in International Arbitration (2013). Note: incorporate the Guidelines by reference so both sides work to the same standard.
  • Decide the form of verification. Authority: IBA Rules art. 4.5(d) (affirmation of truth). Note: in a U.S.-seated case some parties use the unsworn declaration form of 28 U.S.C. § 1746 for consistency with any later court proceedings, though the tribunal does not require it.
  • Address expert instructions and drafts. Authority: IBA Rules art. 5.2(b) (description of instructions). Note: there is no counterpart to the draft-report protection of Fed. R. Civ. P. 26(b)(4) unless PO1 creates one. Propose a clause that drafts and counsel-expert communications are not disclosable, but instructions are.
  • Provide for expert meetings and a joint report. Authority: IBA Rules art. 5.4. Note: specify whether counsel may attend, whether the meeting is without prejudice, and the format of the joint statement (issues agreed, issues disagreed, reasons).
  • Reserve the tribunal's power to appoint an expert, and say how. Authority: IBA Rules art. 6; ICC Rules art. 25(4); UNCITRAL Rules art. 29; LCIA Rules art. 21.
  • Provide for witness conferencing. Authority: IBA Rules art. 8 (testimony may be arranged by issue, with witnesses questioned at the same time and in confrontation with each other).
  • Settle sequestration. Note: unlike Fed. R. Evid. 615, there is no default exclusion rule. Decide whether fact witnesses may attend before testifying and whether party representatives who are witnesses may attend throughout.
  • Adopt a rule on contact during testimony. Note: once cross-examination begins, counsel should not discuss the substance of testimony with the witness until it ends. U.S. courts apply a similar rule in depositions (Hall v. Clifton Precision, 150 F.R.D. 525 (E.D. Pa. 1993)).
  • Address remote testimony now. Authority: IBA Rules art. 8.2 (remote hearing protocol); ICC Rules art. 26(1); LCIA Rules art. 19; UNCITRAL Rules art. 28(4). Note: protocol items include platform, testing, time zones, document display, and safeguards against coaching.
  • Address cybersecurity and data protection. Authority: IBA Rules art. 2.2(e); ICCA-NYC Bar-CPR Protocol on Cybersecurity in International Arbitration (2020); ICCA-IBA Roadmap to Data Protection in International Arbitration (2022).
  • Fix the hearing time allocation. Note: chess-clock allocation is standard; agree whether direct examination counts against the examining party's time.

Red flag: no PO1 rule on expert instructions or drafts. If the order is silent, the other side may ask for the instruction letter and the expert's working drafts. Fix the rule before experts are retained, or draft every communication as if the tribunal will read it.

Phase 2: Identify and interview fact witnesses

  • Map who knows what. List each disputed fact and the people with first-hand knowledge on both sides, including former employees and third parties.
  • Remember that party representatives can testify. Authority: IBA Rules art. 4.2; UNCITRAL Rules art. 27(2). Note: civil-law counterparts may assume their directors cannot be witnesses; in arbitration they can, and the tribunal weighs their interest.
  • Interview within the professional rules. Authority: IBA Rules art. 4.3; IBA Guidelines on Party Representation (provisions on witnesses and experts). Note: counsel may discuss prospective testimony; counsel must not invite false testimony or suggest content the witness does not know.
  • Check counsel's home-jurisdiction rules. Note: English barristers may not coach witnesses, and some civil-law bars historically restricted pre-hearing contact. Know the limits that bind each member of your team, including local co-counsel.
  • Give the witness the right explanation. Note: tell the witness that the statement is their evidence, that they must be able to defend every sentence under cross-examination, and that they may and should tell the truth even where it hurts the case.
  • Interview with documents. Note: show the witness the key contemporaneous documents; record which documents the witness saw before and which they are seeing for the first time.
  • Identify witnesses you cannot control. Note: former employees and third parties may refuse. Consider whether a section 7 summons is available (U.S. seat only; see Phase 8) or whether court assistance at the seat is needed.
  • Decide not to call some witnesses. Note: every witness offered is a cross-examination target. A weak witness on a peripheral point can damage credibility on the central issues.
  • Consider interpreters early. Note: a witness who will testify through an interpreter should prepare a statement in their own language, translated, rather than an English statement they cannot fully read.

Red flag: the witness who learned the facts from counsel. If a witness's knowledge of a point comes from documents counsel showed them, the statement must say so. Article 4.5(b) requires the source of the witness's information. A statement that presents second-hand information as first-hand is a gift to the cross-examiner.

Phase 3: Draft the witness statements

  • Include every Article 4.5 element. Authority: IBA Rules art. 4.5. Checklist within the checklist:
    • Full name and address.
    • Present and past relationship with any party.
    • Background, qualifications, training, and experience, if relevant.
    • Full and detailed description of the facts, and the source of the witness's information.
    • Documents relied on that have not already been submitted.
    • Language in which the statement was prepared and the language of anticipated oral testimony.
    • Affirmation of truth.
    • Signature, date, and place.
  • Write in the witness's voice. Note: work from interview notes; use the witness's vocabulary; avoid legal conclusions and argument. A tribunal that suspects a statement is counsel's advocacy gives it little weight.
  • Separate observation from inference. Note: "I attended the 12 March meeting. Mr. Novák said..." is evidence. "It was clear that Respondent had already decided to terminate" is argument unless the witness explains why.
  • Cite contemporaneous documents for every important fact. Note: tribunals in international cases generally trust documents over recollection. Anchor testimony to exhibits by number.
  • Deal with the bad documents. Note: if an exhibit contradicts the witness, address it in the statement. Silence invites the cross-examiner to raise it first.
  • Keep it as short as the facts allow. Note: length signals counsel drafting. Twenty focused pages beat sixty.
  • Have the witness read and correct every draft. Note: record the witness's changes; tribunals sometimes ask witnesses how the statement was prepared.
  • Translate faithfully. Note: if the statement was prepared in another language, file both versions and identify the original. Authority: IBA Rules art. 4.5(c).
  • Check consistency across statements. Note: identical phrasing in two witnesses' statements suggests a common drafter and invites cross-examination on preparation.
  • Remember that failure to appear can erase the statement. Authority: IBA Rules art. 4.7 (the tribunal shall disregard the statement of a witness who fails without valid reason to appear when requested, unless in exceptional circumstances it decides otherwise). Note: confirm availability for the hearing dates before filing.

Phase 4: Respond to the other side's witnesses

  • Analyze each opposing statement against the documents. Note: chart each factual assertion, its source, and any contradicting exhibit.
  • Decide whether to call each opposing witness for cross-examination. Authority: IBA Rules arts. 4.8 and 8.1. Note: under Article 4.8, not calling a witness does not mean accepting the statement, but an unchallenged statement may still be given weight. Call the witnesses whose evidence matters.
  • Use reply statements to answer new points. Authority: IBA Rules art. 4.6.
  • Consider document requests prompted by statements. Note: documents a witness refers to but the party has not produced are prime targets for a narrow request, and failure to produce them may support an inference under IBA Rules art. 9.6 or 9.7.
  • Object to inadmissible or improper statements early. Note: if a statement contains legal argument, expert opinion from a fact witness, or matters outside the witness's knowledge, ask the tribunal to disregard those passages, or at least flag the issue for weight.
  • Plan cross-examination chapters. Note: adapt U.S. technique to a tribunal: shorter, document-driven, fewer leading-question loops. See the Cross-Examination Preparation Checklist: A Practical Checklist.

Phase 5: Select and instruct party-appointed experts

  • Define the expert issues from the pleadings. Note: liability (technical, industry practice, foreign law where the tribunal wants evidence of it) and quantum are usually separate experts.
  • Check independence before retention. Authority: IBA Rules art. 5.2(a) and (c) (relationships with parties, counsel, and the tribunal; statement of independence). Note: ask about prior engagements for or against the parties and their affiliates, and about any relationship with a member of the tribunal.
  • Check conflicts with the tribunal. Authority: IBA Guidelines on Conflicts of Interest in International Arbitration (2014; a revised edition was adopted in 2024). Note: these govern arbitrators, but a close relationship between an arbitrator and your expert may require disclosure and, if introduced late, could prompt the tribunal to exclude the expert to protect the award.
  • Check the expert's arbitral experience. Note: an expert who has testified only in U.S. courts may be unfamiliar with joint meetings and conferencing. Ask whether they have done both.
  • Write the instruction letter for the tribunal. Authority: IBA Rules art. 5.2(b). Note: state the questions neutrally, list the documents provided, set out assumptions to be made and why, and remind the expert of the duty of independence.
  • Agree fees that are not contingent. Authority: IBA Guidelines on Party Representation (compensation of witnesses and experts). Note: hourly or fixed fees only; contingent fees destroy credibility and may breach professional rules.
  • Provide the record, not a curated subset. Note: an expert who was not shown key adverse documents will be cross-examined on them. Provide the full exhibit record and relevant produced documents.
  • Plan for the foreign-law question. Note: some tribunals expect foreign law to be proved by expert evidence; others apply iura novit curia and want legal submissions instead. Ask in PO1.
  • Remember there is no Daubert motion. Note: arbitrators are not bound by Fed. R. Evid. 702, Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), or Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999). Methodology attacks go to weight. Build your critique into your own expert's reply report and cross-examination, not into an exclusion motion. For the court-side comparison, see Expert Witnesses After the 2023 Amendment to Rule 702: Daubert, Disclosure, and Cross-Examination.

Red flag: the advocate-expert. An expert who adopts counsel's case theory wholesale, refuses to concede obvious points, or uses the pleading's language will be exposed at a joint meeting or in conferencing. Choose experts who can disagree with you in private and concede gracefully in public.

Phase 6: Expert reports, replies, and joint meetings

  • Include every Article 5.2 element in each report. Authority: IBA Rules art. 5.2. Checklist within the checklist:
    • Name, address, relationships with parties, counsel, and tribunal; background and qualifications.
    • Description of instructions.
    • Statement of independence.
    • Facts on which the opinions are based.
    • Opinions and conclusions, with methods, evidence, and information used.
    • Documents relied on.
    • Statement on language and translation, if applicable.
    • Affirmation of genuine belief in the opinions.
    • Signature, date, and place; attribution among co-authors.
  • Make assumptions explicit. Note: where the expert assumes a disputed fact, say so and cross-refer to the witness evidence. Tribunals decide facts, then choose the expert who assumed correctly.
  • Provide a model the tribunal can run. Note: quantum experts should supply working spreadsheets so the tribunal can change inputs. Tribunals often adopt one expert's model with the other's assumptions.
  • Limit reply reports to response. Authority: IBA Rules art. 5.3.
  • Prepare for the joint meeting. Authority: IBA Rules art. 5.4. Note: the expert, not counsel, negotiates. Agree beforehand what the expert may concede.
  • Produce a usable joint statement. Note: a table of issues, each with "agreed" or "not agreed," each expert's position, and the reason for disagreement. This becomes the agenda for conferencing.
  • Check consistency with the damages theory. Note: see the Damages Proof and Expert Model Checklist: A Practical Checklist for model-integrity tasks that transfer to arbitration.

Phase 7: Tribunal-appointed experts

  • Decide whether to propose or oppose a tribunal expert. Authority: IBA Rules art. 6.1; ICC Rules art. 25(4); UNCITRAL Rules art. 29(1); LCIA Rules art. 21; UNCITRAL Model Law art. 26. Note: a tribunal expert may favor the party with the technically stronger case; it also adds cost and time.
  • Negotiate the terms of reference. Note: the questions put to the expert decide much of the outcome. Propose neutral, specific questions.
  • Scrutinize the statement of independence and object in time. Authority: IBA Rules art. 6.2; UNCITRAL Rules art. 29(2).
  • Supply information promptly and completely. Authority: IBA Rules art. 6.3. Note: requests from the tribunal expert carry the tribunal's authority; a refusal can support an inference.
  • Comment on the report in writing. Authority: IBA Rules art. 6.5; UNCITRAL Rules art. 29(4). Note: use your own expert to prepare the comments.
  • Question the tribunal expert at the hearing. Authority: IBA Rules art. 6.6; UNCITRAL Rules art. 29(5). Note: the tribunal expert's opinion does not bind the tribunal, which assesses it with the rest of the evidence (IBA Rules art. 6.7).
  • Consider expert teaming as a compromise. Note: under the protocol associated with Klaus Sachs, the tribunal picks one expert from each party's list to form a joint tribunal-appointed team. Offer it when both sides distrust a single tribunal expert.

Phase 8: Prepare for the hearing

  • Serve the witness notification on time. Authority: IBA Rules art. 8.1 (each party informs the tribunal and the other parties of the witnesses whose appearance it requests). Note: missing this deadline can mean losing the right to cross-examine.
  • Confirm availability, travel, and visas. Note: Article 4.7 makes availability your problem. A witness who cannot travel should be offered by video, with the tribunal's leave, well in advance.
  • Prepare witnesses for cross-examination. Authority: IBA Rules art. 4.3; IBA Guidelines on Party Representation. Note: practice with documents, explain the format, show the hearing room or platform, and rehearse listening to the question. Do not script answers.
  • Prepare the witness for an interpreter. Note: brief the interpreter on technical vocabulary; ask the witness to answer in their own language even if they speak some English.
  • Settle the remote testimony protocol. Authority: IBA Rules art. 8.2. Note: camera showing the witness and the room, no other applications open, a clean copy of the hearing bundle, a statement that no one else is present, and a rule on breaks. Tools that work in remote depositions transfer; see the Remote Deposition Checklist: A Practical Checklist.
  • For a nonparty witness in a U.S.-seated case, consider a section 7 summons. Authority: 9 U.S.C. § 7. Note: section 7 compels attendance before the arbitrators; it is enforced by the district court where the arbitrators sit, and the FAA does not authorize nationwide service (Dynegy Midstream Services, LP v. Trammochem, 451 F.3d 89 (2d Cir. 2006)). Most circuits do not permit pre-hearing depositions or document discovery of nonparties under section 7 (Hay Group, Inc. v. E.B.S. Acquisition Corp., 360 F.3d 404 (3d Cir. 2004); Life Receivables Trust v. Syndicate 102 at Lloyd's of London, 549 F.3d 210 (2d Cir. 2008)), though a nonparty can be compelled to testify at a hearing before the panel that is not the final hearing (Stolt-Nielsen SA v. Celanese AG, 430 F.3d 567 (2d Cir. 2005)).
  • Do not plan on section 1782 for a private arbitration. Authority: 28 U.S.C. § 1782; ZF Automotive US, Inc. v. Luxshare, Ltd., 596 U.S. 619 (2022). Note: the statute does not reach private commercial tribunals.
  • For a nonparty witness outside the United States, check the seat's law. Authority: UNCITRAL Model Law art. 27; English Arbitration Act 1996 ss. 43 and 44 (as amended by the Arbitration Act 2025). Note: confirm whether the seat's courts can compel a witness located in that country.
  • Prepare the expert conferencing agenda. Note: work from the joint statement's list of disagreements. Propose the order of issues and time per issue.
  • Prepare demonstratives and core bundles. Note: tribunals expect a core bundle of key documents and may limit new demonstratives; agree a deadline for exchange.
  • Brief the witness on documents used to refresh memory. Note: tribunals may ask what the witness reviewed in preparation; answer honestly. U.S. litigators will recognize the issue from Fed. R. Evid. 612.

Red flag: the witness who has never read the other side's evidence. A witness who is surprised at the hearing by an opposing statement or a contradictory exhibit performs badly. Every witness should review the other side's statements on their topics and the key adverse documents before testifying.

Phase 9: At the hearing

  • Keep direct examination short. Note: most tribunals allow 10 to 15 minutes to confirm the statement, correct errors, and address new matters. Use it to humanize the witness and to answer points raised since the last statement.
  • Confirm corrections at the start. Note: correct errors in the statement before cross-examination begins; corrections extracted on cross look worse.
  • Cross-examine to documents. Note: put the document, take the admission, move on. Tribunals dislike repetitive questioning, and Article 8 gives them control to limit or exclude questions.
  • Respect the no-contact rule. Note: do not discuss the substance of testimony with a witness during breaks while cross-examination is ongoing.
  • In conferencing, let the experts talk. Authority: IBA Rules art. 8. Note: the tribunal usually leads; counsel's cross-examination comes at the end of each issue or after the session. Prepare short, surgical questions, not a full cross.
  • Use redirect sparingly. Note: limited to matters raised in cross; long redirect signals damage.
  • Answer the tribunal's questions directly. Note: the questions tell you what the tribunal thinks matters. Note them for closing submissions.
  • Object on the record, briefly, when needed. Note: if the tribunal excludes evidence or limits a witness in a way you regard as unfair, state the objection and the prejudice, and ask for a cure. A court reviewing an award will look for this.
  • Monitor the chess clock. Note: leave time for the witnesses that matter most.

Phase 10: After the hearing, and protecting the record

Deadlines table

Exact deadlines come from PO1 and the procedural timetable. The table shows the usual sequence and typical intervals.

Event Typical timing Authority Consequence of missing it
Witness and expert provisions agreed First case management conference IBA Rules art. 2; ICC Rules art. 24 Default rules or tribunal's discretion govern
First witness statements and expert reports With statement of claim or memorial IBA Rules arts. 4.4, 5.1 Late evidence needs leave
Responsive statements and reports With statement of defense or counter-memorial IBA Rules arts. 4.4, 5.1 Same
Reply statements and reports With reply and rejoinder IBA Rules arts. 4.6, 5.3 Limited to responsive matters
Expert joint meeting and joint statement 4-8 weeks before hearing IBA Rules art. 5.4 Tribunal may order it later; hearing less focused
Notification of witnesses to be cross-examined Usually 4-6 weeks before hearing IBA Rules art. 8.1 Right to cross-examine may be lost
Remote hearing protocol and test 2-4 weeks before hearing IBA Rules art. 8.2 Risk of disruption; due-process objection
Core bundle and demonstratives 1-2 weeks before hearing PO1 Exclusion or limited use
Section 7 summons (U.S. seat) Well before the hearing, to allow enforcement 9 U.S.C. § 7 Witness may not appear
Post-hearing briefs 4-8 weeks after hearing PO1 Waiver of points not made
Motion to vacate (U.S. seat) Within three months after the award is filed or delivered 9 U.S.C. § 12 Challenge barred

Common failure points and a short worked example

Failure points.

  1. Counsel-drafted statements. The witness cannot explain words in their own statement.
  2. No preparation on adverse documents. The witness sees the worst email for the first time on cross.
  3. Late discovery of unavailability. A key witness cannot travel, and the statement is disregarded under Article 4.7.
  4. Experts who will not concede. A joint meeting with no agreed issues signals an advocate-expert to the tribunal.
  5. Instructions written for the client, not the tribunal. The letter is ordered produced and reads like a brief.
  6. Missing the witness notification. A party loses the chance to cross-examine a central witness.
  7. No record of objections. A party later argues it was unable to present its case but never told the tribunal so.

Worked example. Halden Grid AS, a Norwegian transmission operator, claims against Marlow Cable Systems Ltd., an English manufacturer, for failures in a subsea cable, in an ICC arbitration seated in Paris. Marlow's key fact witness is its former head of quality, now retired in Spain, who drafted the factory acceptance tests. Marlow's counsel interview him in Spanish, with documents, and prepare his statement in Spanish with a certified English translation, both filed, noting the original language under Article 4.5(c). Because he is not willing to travel to Paris, counsel raise remote testimony at the pre-hearing conference, and the tribunal orders a remote examination with a protocol requiring a fixed camera, a sealed hard-copy bundle opened on screen, and an interpreter in the hearing room. Halden's quantum expert and Marlow's quantum expert meet under Article 5.4 and agree on the cost of cable repair but not on the business-interruption claim; their joint statement lists five disagreements. At the hearing, the tribunal conferences the experts for half a day on those five issues; Halden's expert concedes one, and the tribunal adopts Marlow's expert's method on two others. Marlow later considers challenging the award on the ground that the tribunal limited its cross-examination of Halden's operations director, but its post-hearing brief never objected to the limit, and its counsel advise that the challenge would fail.

This document is general information, not legal advice for any particular situation; arbitral rules, national law, and tribunal practice vary, and the facts matter.

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