Arbitrator Conflict of Interest: How to Request Replacement

Arbitrator Conflict of Interest: Grounds, Challenge Procedure, and Proof Strategy

Mid-arbitration, you discover the arbitrator appointed by the other side used to be regular counsel to their group — and never disclosed it. The award is about to issue. A challenge is your most important right at this moment — but also the easiest procedure to lose if handled wrongly.

Contents

• 1. Why arbitrator conflicts are existential
• 2. The four challenge grounds under Article 42
• 3. The arbitrator's disclosure duty
• 4. Procedure and deciding authority
• 5. Proof strategy: how to win a challenge
• 6. If the challenge fails: the annulment route
• 7. FAQs
• 8. When to work with a lawyer

1. Why arbitrator conflicts are existential

Commercial arbitration exists on trust: parties abandon national courts for individuals they believe impartial. An unaddressed conflict collapses that trust — worse, it creates grounds to annul the award later, wasting all arbitration time and cost.

2. The four challenge grounds under Article 42

Article 42 of the 2010 Law on Commercial Arbitration provides for arbitrator replacement. Parties may challenge on these grounds:

1. Being a relative or representative of a party — family or direct representation creates obvious doubt about impartiality.
2. Having related interests in the dispute — e.g., shareholding in a party, financial ties to a disputant.
3. Clear grounds of lacking impartiality and objectivity — an open-ended ground covering biased conduct during proceedings, public statements about the case, or close professional ties with a party.
4. Having acted as mediator, representative, or lawyer for a party in the same dispute without written consent of all parties — the classic "role-switch" case.

3. The arbitrator's disclosure duty

Arbitrators must promptly notify parties of any circumstances that may raise justifiable doubts about their impartiality and objectivity — past work relationships, financial ties, prior legal opinions on disputed issues.

Consequences of non-disclosure are severe: (1) direct grounds for challenge; (2) if discovered after the award, grounds to annul the award in court; (3) impaired recognition and enforcement abroad.

4. Procedure and deciding authority

Challenges must be in writing, state grounds with evidence, and be filed promptly after learning (or being deemed to know) the grounds.

Deciding authority depends on arbitration type and stage:

• Institutional arbitration, tribunal not yet constituted: the arbitration centre decides.
• Tribunal constituted: the remaining arbitrators decide (unless the challenge concerns several members).
• Ad hoc arbitration: per party agreement and law; parties should agree this mechanism in the arbitration clause upfront.

Note: each institution's rules (VIAC, SIAC, HKIAC, ICC…) may differ on deadlines and procedure — always check the applicable rules.

5. Proof strategy: how to win a challenge

Challenges based on vague suspicion are usually rejected. Effective strategy:

1. Concrete evidence, not speculation: documents proving the relationship (old retainer contracts, ownership structures, emails…) — not "we feel bias."
2. Objective standard: show a reasonable third person, fully informed, would harbor justifiable doubts — the standard applied in international arbitration practice.
3. Timeliness: challenge immediately upon discovery; unjustified delay equals waiver.
4. No abuse: tactical challenges (delay, pressure) damage the requesting party's credibility before the tribunal if exposed.

6. If the challenge fails: the annulment route

If a challenge is rejected but the conflict is real, the affected party may still seek court annulment of the award — on grounds the tribunal's composition breached party agreement or law. But courts annul only in statutory cases; failing to challenge timely during proceedings significantly weakens later annulment prospects. Hence a timely challenge is an unskippable step.

Practice at VIAC. The Vietnam International Arbitration Centre's rules detail challenge procedures, including filing deadlines and form. Companies agreeing on VIAC should read the current challenge provisions when drafting the arbitration clause — not when a conflict surfaces. And when appointing arbitrators, do reasonable background checks: public records of work relationships, publications, and past cases. Spotting a conflict early is always cheaper than litigating it mid-proceedings.

Documenting the challenge file. A challenge succeeds or fails on its paper trail. Build the file as you go: the arbitrator's disclosure (or lack thereof), dated evidence of the undisclosed relationship, correspondence showing when your side first learned of it, and a short memo linking each fact to the specific Article 42 ground invoked. Decision-makers respond to organized chronologies, not to indignation — and a well-built challenge file doubles as the record for any later award-annulment action if the challenge is denied.

7. FAQs

Q: What are the grounds for challenging an arbitrator?

A: Under Article 42 of the 2010 Law on Commercial Arbitration, parties may challenge an arbitrator who: is a relative or representative of a party; has related interests in the dispute; shows clear grounds of lacking impartiality and objectivity; or previously acted as mediator, representative, or lawyer for a party without written consent of all parties.

Q: Must arbitrators disclose conflicts of interest?

A: Yes. Arbitrators must disclose to the parties any circumstances that may raise justifiable doubts about their impartiality and objectivity. Failure to disclose material information can ground a challenge and later an award-annulment action.

Q: Who decides an arbitrator challenge?

A: It depends on the stage: if the tribunal is not yet constituted, the arbitration centre (for institutional arbitration) decides; if constituted, the remaining arbitrators decide (unless the challenge concerns several members). For ad hoc arbitration, the mechanism follows party agreement and law.

Q: Is there a time limit for challenging an arbitrator?

A: Yes. Challenges must be raised promptly after the requesting party knew or should have known the grounds. Unjustified delay may be treated as waiver — and weakens later annulment attempts on the same grounds.

8. When to work with a lawyer

Work with a lawyer when: discovering signs of arbitrator conflict and needing assessment of grounds, evidence gathering, and challenge drafting; designing arbitration clauses at contract stage (appointment and replacement mechanisms); or seeking award annulment over tribunal-composition defects. FLAT Law Firm represents clients in VIAC, SIAC, HKIAC arbitrations — hotline 0988424851.

References

• 2010 Law on Commercial Arbitration (No. 54/2010/QH12), effective 1/7/2011.
• Cross-checked via thuvienphapluat.vn and ASL Law analysis as of drafting (28/9/2026).

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