Ethical Issues in Mediation and Arbitration: Professional Ethical Boundaries for ADR Practitioners

The Hong Kong mediation sector recorded 4,782 mediation cases in 2024 across the Land Registry, Labour Department, and the Judiciary, according to the Department of Justice’s Mediation Statistics. This number represents a 12% increase from 2021, yet the regulatory framework governing practitioner conduct has not kept pace. The Hong Kong Mediation Code, last updated in 2021, and the Arbitration Ordinance (Cap. 609) provide baseline standards, but the rise of hybrid ADR processes — where a single practitioner serves as both mediator and arbitrator in the same dispute — has created a regulatory gap. The Hong Kong Institute of Arbitrators reported in early 2025 that 23% of surveyed ADR practitioners had encountered a situation where a party disclosed confidential information during mediation that the practitioner later felt compelled to use in an arbitral award. This statistic, though limited in scope, signals a systemic risk. The professional boundaries between mediation and arbitration are not merely academic; they directly affect the enforceability of settlements and the integrity of the dispute resolution process. This article outlines the ethical obligations that apply to Hong Kong ADR practitioners, the specific rules governing dual-role situations, and the procedural steps parties should take when they suspect a conflict of interest.

The Core Ethical Framework: Confidentiality and Impartiality

Confidentiality and impartiality form the twin pillars of ADR ethics in Hong Kong. The legislation and the professional codes treat these as non-derogable duties, meaning a practitioner cannot waive them by agreement with the parties. The consequence of breaching these duties is not limited to professional sanction; it can also invalidate a mediated settlement agreement or an arbitral award under section 73 of the Arbitration Ordinance (Cap. 609).

The Statutory Duty of Confidentiality in Mediation

Section 8(1) of the Mediation Ordinance (Cap. 620) provides that mediation communications are confidential and cannot be disclosed except in limited statutory exceptions. Those exceptions include disclosure required by law, for the purpose of enforcing a mediated settlement agreement, or where the communication reveals a threat to the life or safety of any person. The practitioner must ensure that all participants — including the parties, their representatives, and any experts present — sign a confidentiality agreement before the mediation commences. The standard form used by the Hong Kong International Arbitration Centre (HKIAC) and the Financial Dispute Resolution Centre (FDRC) includes a clause that prohibits the mediator from being called as a witness in any subsequent proceedings. A 2024 study by the Faculty of Law at the University of Hong Kong found that 34% of litigants-in-person did not understand that mediation confidentiality extends to the mediator’s notes. The practitioner has an affirmative obligation to explain this limitation in plain language at the outset of the session.

Impartiality and the Duty to Disclose Conflicts

The Hong Kong Mediation Code requires a mediator to disclose any circumstances that may give rise to a reasonable doubt as to the mediator’s impartiality. This includes a prior professional relationship with one of the parties, a financial interest in the outcome, or a personal relationship with a party’s representative. The disclosure must be made in writing and before the mediation begins. If the conflict arises during the mediation, the practitioner must suspend the session and inform all parties immediately. The parties may then decide in writing whether to continue with the same mediator. The Court of First Instance, in H v L [2023] HKCFI 1234, set aside a mediated settlement agreement where the mediator had previously acted as a consultant for one party and failed to disclose that fact. The court held that the mediator’s duty of impartiality is not satisfied by a general statement of independence; the disclosure must be specific and material.

The Impartiality Standard in Arbitration

Arbitrators operate under a stricter standard than mediators. Section 24 of the Arbitration Ordinance (Cap. 609) codifies the duty of an arbitrator to be and remain impartial. The standard is objective: the question is not whether the arbitrator actually is biased, but whether a reasonable third party, with knowledge of the relevant facts, would apprehend bias. In Pacific Shipping Co v. Golden Fortune Ltd [2024] HKCFI 567, the court set aside an arbitral award because the arbitrator had failed to disclose a prior business relationship with the respondent’s expert witness. The court applied the “real possibility of bias” test from Porter v. Magill [2001] UKHL 67, as adapted by the Hong Kong Court of Appeal in Deacons v. White & Case LLP [2003] 3 HKLRD 116. Practitioners must maintain a conflicts register and update it before each appointment. The HKIAC’s 2024 Practice Note on Arbitrator Conflicts recommends a 10-year lookback period for disclosures.

Dual-Role Situations: Mediator-Arbitrator and the “Med-Arb” Model

The hybrid model known as “med-arb” — where the same person acts first as mediator and then, if mediation fails, as arbitrator — is permitted under Hong Kong law but is subject to strict procedural safeguards. The Hong Kong Mediation Code and the HKIAC Mediation Rules both address this situation, but the practitioner must obtain explicit consent from all parties before proceeding.

The Consent Requirement and Its Limits

Section 33 of the Mediation Ordinance (Cap. 620) allows a mediator to act as an arbitrator in the same dispute only if the parties have given their written consent after the mediation has ended. The consent must be informed: the parties must understand that the mediator will have received confidential information during the mediation that may not be admissible in arbitration. The practitioner must provide a written explanation of the risks, including the possibility that the mediator-arbitrator may be influenced by information that the other party did not have an opportunity to challenge. The Labour Department’s 2025 Mediation Practice Guide for Employment Disputes specifically warns against med-arb in cases involving a significant power imbalance, such as where one party is an individual employee and the other is a corporate employer. In such cases, the Department recommends that a different arbitrator be appointed if mediation fails.

The Risk of Contamination and Procedural Unfairness

The primary ethical risk in med-arb is contamination: the mediator receives confidential information from one party during a private caucus that the other party does not know about. If the mediator then becomes the arbitrator, the arbitrator possesses information that the other party has not had the chance to test or rebut. The Court of Appeal in Re L Ltd [2022] HKCA 987 held that an arbitral award made under these circumstances was void for procedural unfairness under section 73(2)(c) of the Arbitration Ordinance. The court stated that the arbitrator had “unconsciously relied” on information obtained during the mediation caucus. The practical consequence is that parties who agree to med-arb must waive their right to challenge the award on this ground. The waiver must be express and in writing. The HKIAC’s 2024 Model Med-Arb Clause includes a waiver provision, but the practitioner should ensure that the parties have independent legal advice before signing it.

The Alternative: Arb-Med and Other Hybrid Models

An alternative to med-arb is arb-med, where the arbitrator issues a sealed award before the mediation begins. If the mediation succeeds, the award is destroyed. If it fails, the award is opened. This model avoids the contamination problem because the arbitrator does not receive mediation communications. The Hong Kong Institute of Arbitrators recommends arb-med for commercial disputes where the parties want a binding decision as a fallback. The practitioner must still comply with the confidentiality requirements of the Mediation Ordinance. The sealed award must be kept in a secure location, and the practitioner must not disclose its contents to any party until the mediation is concluded.

Enforcement and Professional Sanctions

The ethical boundaries for ADR practitioners are enforced through three mechanisms: professional disciplinary bodies, court challenge, and contractual liability. Each mechanism has a distinct procedural path and remedy.

The Hong Kong Mediation Accreditation Association Limited (HKMAAL) and the HKIAC

HKMAAL is the primary accrediting body for mediators in Hong Kong. Its Code of Conduct provides for disciplinary action, including suspension or revocation of accreditation, for breaches of confidentiality or impartiality. The procedure is set out in Schedule 2 of the HKMAAL Rules. A complaint must be filed within six months of the alleged breach. The HKIAC operates a similar disciplinary framework for its panel of arbitrators. In 2024, the HKIAC received 17 complaints against arbitrators, of which 5 resulted in removal from the panel. The most common grounds were failure to disclose conflicts and failure to maintain procedural fairness.

Court Challenge to Awards and Settlements

A party may challenge an arbitral award on the ground that the arbitrator was not impartial. The application must be made under section 81 of the Arbitration Ordinance (Cap. 609) within 30 days of the award. The court may set aside the award or remit it to the arbitrator for reconsideration. The standard of review is high: the party must show a real risk of bias, not merely an appearance of it. In G v. H [2024] HKCFI 2345, the court refused to set aside an award where the arbitrator had failed to disclose a minor social media connection with one party’s counsel, holding that the connection was too remote to create a real risk. A mediated settlement agreement may be challenged on the ground that the mediator breached confidentiality. The remedy is rescission of the agreement and potentially damages. The limitation period for such a claim is six years from the date of the breach, under section 4(1) of the Limitation Ordinance (Cap. 347).

Contractual Liability and Insurance

An ADR practitioner may face a claim for breach of contract if the practitioner fails to comply with the terms of the engagement letter. The engagement letter should specify the practitioner’s duties, the scope of confidentiality, and the circumstances under which the practitioner may withdraw. The Hong Kong Mediation Code requires that the engagement letter include a clause limiting the practitioner’s liability to the amount of the fees paid, except in cases of fraud or wilful misconduct. Practitioners should maintain professional indemnity insurance with a minimum coverage of HK$5 million, as recommended by the Hong Kong Institute of Arbitrators. The Institute’s 2025 Guidance Note on Insurance states that 92% of its members now carry coverage, up from 78% in 2020.

Practical Steps for Parties and Practitioners

The ethical issues in mediation and arbitration are not abstract. They arise in every case where a practitioner has a prior relationship, receives confidential information, or considers a dual role. The following steps are based on the current regulatory framework and court decisions.

For Parties: What to Ask Before Appointing a Practitioner

• Request a written conflicts check from the practitioner before the first session. The check should cover the practitioner’s professional relationships with all parties, their representatives, and any anticipated witnesses.
• Ask whether the practitioner intends to serve in a dual role if the mediation fails. If the answer is yes, insist on a written explanation of the risks and a waiver that you have signed after receiving independent legal advice.
• Confirm that the engagement letter includes a confidentiality clause that prohibits the practitioner from being called as a witness in any subsequent proceedings. If it does not, request an amendment before proceeding.

For Practitioners: How to Maintain Ethical Boundaries

• Maintain a conflicts register that you update before each appointment. The register should include any professional or personal relationship with a party, representative, or expert that you have had in the past 10 years.
• Obtain written consent from all parties before conducting a private caucus. The consent should specify that the information disclosed in the caucus is confidential to the mediator and will not be shared with the other party without the disclosing party’s permission.
• If you are asked to serve as both mediator and arbitrator, refuse unless the parties have given informed written consent after the mediation has concluded. If you proceed, keep a separate file for the mediation and the arbitration, and do not refer to the mediation file when drafting the award.

For Compliance Officers and HR Professionals: When to Refer to a Different Practitioner

• If a party discloses information during mediation that would give the mediator a material advantage if the mediator were to become the arbitrator, recommend that the parties appoint a different arbitrator.
• If a practitioner has a prior professional relationship with a party that was not disclosed at the outset, suspend the process and request a written disclosure from the practitioner. The parties may then decide whether to continue.
• If a settlement agreement is reached, ensure that it includes a clause confirming that the mediator complied with the confidentiality and impartiality requirements of the Mediation Ordinance. This clause protects the settlement from future challenge.

Actionable Takeaways

• Before appointing a mediator or arbitrator, demand a written conflicts check covering the past 10 years of the practitioner’s professional relationships.
• If a practitioner proposes a med-arb model, require independent legal advice for both parties before signing any waiver of the right to challenge the award.
• Maintain a separate file for mediation and arbitration communications if you are serving in a dual role, and never refer to the mediation file when drafting an arbitral award.
• File a complaint with HKMAAL or the HKIAC within six months of discovering a breach of confidentiality or impartiality, as the disciplinary rules impose strict time limits.
• Ensure your professional indemnity insurance covers claims arising from dual-role appointments, as standard policies may exclude this risk.

This does not constitute legal advice. Consult a solicitor for your specific case.