International arbitration is often chosen because it offers parties a final and enforceable decision.[1] In most cases, that finality is one of its greatest advantages. However, an arbitral award is not immune from challenge.[2] Where serious misconduct has affected the proceedings, a party may be able to challenge the arbitral award before the courts of the seat, resist enforcement under the Convention on the Recognition and Enforcement of Foreign Arbitral Awards (the “New York Convention”), or seek procedural remedies before the tribunal while the arbitration is still ongoing. The key question is not only whether misconduct occurred, but whether it was serious enough to affect the fairness of the arbitration, the integrity of the proceedings, or the outcome of the award.[3]
What Types of Misconduct Matter?
Misconduct in arbitration can take many forms. It may involve a party relying on forged documents, concealing material evidence, misusing privileged documents, or presenting false witness testimony. It may involve counsel engaging in abusive tactics, such as late document dumps, misleading submissions, or improper witness interference.[4] It may also involve arbitrator misconduct, including undisclosed conflicts of interest, lack of independence, apparent bias, improper communications with one party, excessive delay, or a failure to give each party a fair opportunity to present its case.[5]
Not every instance of sharp practice will justify post-award relief. International arbitration systems are generally designed to avoid a full appeal on the merits. Courts will usually distinguish between ordinary procedural complaints, which should have been raised before the tribunal, and serious irregularities that strike at the legitimacy of the proceeding. That distinction matters. A losing party cannot usually turn disappointment with the award into a post-award ethics challenge.
Why Misconduct Does Not Automatically Invalidate an Award
Most modern arbitration laws and the New York Convention reflect a pro-enforcement policy.[6] Once an award exists, the starting point is that it should be recognised and enforced. Under the New York Convention, the party resisting enforcement generally bears the burden of proving one of the limited grounds for refusal.[7] Those grounds are interpreted narrowly in many jurisdictions, and recognition proceedings are not meant to become a second arbitration.[8]
This means that misconduct must usually be serious and material. A court is more likely to intervene where the misconduct affected due process, tribunal independence, the agreed procedure, public policy, or the ability of a party to present its case. A court is less likely to intervene where the alleged misconduct is speculative, harmless, known but not objected to during the arbitration, or merely an attempt to reargue the merits.
Challenging the Award at the Seat
The primary route for challenging an award is usually an application to set it aside before the courts of the seat of arbitration. The available grounds depend on the law of the seat. In Model Law jurisdictions, common grounds include lack of proper notice, inability to present one’s case, an arbitral procedure not in accordance with the parties’ agreement or the law of the seat, improper tribunal composition, excess of jurisdiction, non-arbitrability, and conflict with public policy. Some common law systems frame the issue through serious irregularity, arbitrator misconduct, corruption, fraud, or public policy.[9]
Timing is important. Many arbitration laws impose short deadlines for setting-aside applications. A party that knew of a procedural defect during the arbitration but failed to object may be treated as having waived the objection. For clients, this means that suspected misconduct should be assessed immediately. Waiting until an unfavourable award is issued can seriously weaken the challenge.
Resisting Enforcement Abroad
A party may also resist recognition or enforcement of an award in a jurisdiction where the winning party seeks to collect assets. Under the New York Convention, relevant grounds may include inability to present one’s case, improper tribunal composition, failure to follow the parties’ agreed procedure, the award having been set aside at the seat, or violation of the enforcing state’s public policy. However, enforcement courts often approach these defences cautiously because the Convention was designed to facilitate, not frustrate, cross-border enforcement.[10]
Public policy is often invoked but rarely simple. It may cover serious fraud, corruption, bribery, denial of justice, or conduct that offends basic notions of morality and justice. Still, courts generally require strong proof. Mere allegations of unfairness, or disagreement with the tribunal’s assessment of evidence, will not usually be enough.
Fraud and False Evidence: When the Line Is Crossed
Fraud is one of the clearest examples of misconduct that may justify a challenge. If a party obtains an award by relying on knowingly false evidence, forged documents, bribed witnesses, or concealed privileged material, the integrity of the process may be compromised.[11] The English decision in Nigeria v. P&ID is a prominent recent illustration. The English court set aside awards after finding that they had been obtained by fraud and were contrary to public policy. The allegations included bribery, use of false evidence, and unlawful retention and misuse of Nigeria’s privileged documents to monitor its arbitration strategy.[12]
P&ID is exceptional because the misconduct went to the foundation of the awards. It also shows why fraud challenges are difficult. Nigeria had to develop evidence over time, including through proceedings in different jurisdictions. In most cases, a party alleging fraud must prove not only the fraud but also its relevance to the award. The more direct the link between the misconduct and the tribunal’s reasoning, the stronger the challenge.
Arbitrator Misconduct and Conflicts of Interest
Misconduct by an arbitrator is especially serious because it affects the legitimacy of the decision-maker. Arbitrators have duties to decide the case, treat the parties equally, allow each side a fair opportunity to present its case, remain independent and impartial, disclose potential conflicts, maintain confidentiality where required, and conduct the proceedings with reasonable efficiency.[13] Failures in these duties may support an arbitrator challenge during the arbitration or, in serious cases, a post-award challenge.[14]
That said, not every procedural ruling against a party indicates bias. Courts are usually reluctant to infer misconduct from case management decisions alone. The stronger cases involve undisclosed relationships, financial interests, repeat appointments that should have been disclosed, improper ex parte communications, refusal to hear material evidence, or reliance on personal knowledge without allowing the parties to respond.[15]
Abuse of Process and Tactical Misconduct
Some misconduct is subtler than fraud. Abuse of process may occur where a party uses procedural rights for a purpose inconsistent with the purpose of arbitration. Examples include manipulating corporate nationality to obtain treaty protection for a foreseeable dispute, multiplying proceedings to increase the chances of a favourable result, or bringing claims for harassment rather than genuine dispute resolution. As Emmanuel Gaillard observed, these cases are difficult because the conduct may not breach a clear procedural rule, yet it can prejudice the opposing party and undermine orderly dispute resolution.[16]
Tribunals may respond through admissibility rulings, costs sanctions, adverse inferences, exclusion of evidence, consolidation where available, or dismissal of claims in extreme cases. If serious abuse is not addressed during the arbitration, and the resulting award is materially affected, the issue may later become relevant in a set-aside or enforcement challenge, provided it falls within an available ground under the law of the seat or the New York Convention. The challenge will be strongest where the abuse caused procedural unfairness, public policy concerns, or a tribunal decision outside the legitimate scope of arbitration.
Practical Steps for Parties Suspecting Misconduct
A party that suspects misconduct should act quickly and carefully. First, preserve evidence, including correspondence, metadata, document production records, witness materials, and procedural orders.[17] Second, identify whether the issue is best raised immediately before the tribunal, before the arbitral institution, or before the courts of the seat. Third, object promptly and clearly, because silence may later be treated as a waiver. Fourth, seek targeted remedies during the arbitration, such as disclosure orders, exclusion of evidence, adverse inferences, confidentiality protections, or a costs order. Fifth, avoid unsupported allegations of fraud or bad faith. Serious allegations require serious evidence.
Clients should also consider the remedies realistically available. During the arbitration, tribunals may be able to control the procedure, sanction abusive conduct through costs, draw adverse inferences, exclude evidence, or protect confidentiality. After the award, options may include setting-aside proceedings at the seat, resisting enforcement abroad, or, in rare cases, seeking revision or reopening where the applicable law and rules permit it.
Conclusion
Misconduct can lead to an international arbitral award being challenged, but only in serious cases. The key question is whether the conduct affected the fairness, integrity, or enforceability of the award. Courts generally respect arbitral finality and are reluctant to reopen the merits. They are more willing to intervene where the award was procured by fraud, the tribunal was not independent or properly constituted, a party was denied a fair opportunity to present its case, or enforcement would violate public policy.
For parties, the most important lesson is to act early. Misconduct should be documented, assessed under the law of the seat and the applicable rules, and raised promptly. In international arbitration, finality is powerful, but it does not protect awards that are fundamentally tainted by fraud, bias, serious procedural unfairness, or abuse of the arbitral process.
[1] See Aceris Law LLC, Appealing International Arbitration Awards, explaining that most arbitration rules do not permit appeals and that awards are generally final, binding and enforceable.
[2] See Aceris Law LLC, How Enforcement Works: Turning Arbitral Awards into Real-World Results, discussing the importance of enforcement as the practical end stage of arbitration.
[3] V. Sandler Obregón, Duties of the Arbitrator, in International Arbitration in Practice (2025), pp. 493-504; G. Born, International Commercial Arbitration (updated March 2024), Ch. 26.
[4] See also Aceris Law LLC, Counsel Ethics in International Arbitration, discussing the regulation of party representatives and counsel conduct in arbitration.
[5] S. K. Dubey, Misconduct by the Arbitrator / Arbitral Tribunal, 5 July 2025 (last accessed 22 May 2026); E. Muñoz and P. Meza Barocio, Rethinking Arbitrator Immunity, 43(2) J. of Intl. Arb. 173.
[6] See Aceris Law LLC, Recognition, Enforcement and Execution in International Arbitration, distinguishing recognition, enforcement and execution of arbitral awards.
[7] Convention on the Recognition and Enforcement of Foreign Arbitral Awards, 1958, Art. V(1); G. Born, International Commercial Arbitration (3rd ed., updated March 2024), §26.03; see also Aceris Law LLC, Resisting the Enforcement of Arbitral Awards: Article V(1)(a) of the New York Convention, noting that Article V contains exhaustively listed grounds for resisting recognition and enforcement.
[8] G. Born, International Commercial Arbitration (updated March 2024), Ch. 26, § 26.03.
[9] L. Nottage, Deference from National Courts to Tribunals, in Deference in International Commercial Arbitration (2023), pp. 141-182.
[10] G. Born, International Commercial Arbitration (updated March 2024), Ch. 26; L. Nottage, Deference from National Courts to Tribunals, in Deference in International Commercial Arbitration (2023), pp. 143-145.
[11] Y. Hortoğlu, The Federal Republic of Nigeria v. Process & Industrial Developments Limited (P&ID), 41(3) Arb. Intl. 633, pp. 633-646; see also Aceris Law LLC, Admissibility of Illegally Obtained Evidence in International Arbitration, explaining that tribunals balance the right to be heard, privacy, good faith and public policy when addressing illegally obtained evidence.
[12] Y. Hortoğlu, The Federal Republic of Nigeria v. Process & Industrial Developments Limited (P&ID), 41(3) Arb. Intl. 633, pp. 633-646.
[13] V. Sandler Obregón, Duties of the Arbitrator, in International Arbitration in Practice (2025), pp. 497-500; see also Aceris Law LLC, 2024 IBA Guidelines on Conflicts of Interest in International Arbitration, noting that undisclosed conflicts may result in annulment or unenforceability of an award.
[14] V. Sandler Obregón, Duties of the Arbitrator (2025), pp. 497-499; E. Muñoz and P. Meza Barocio, Rethinking Arbitrator Immunity, 43(2) J. of Intl. Arb. 173, pp. 173-210.
[15] See Aceris Law LLC, The Impartiality Test: How Unbiased Can an Arbitrator Truly Be?, discussing relationships with parties or counsel, disclosure and apparent bias.
[16] E. Gaillard, Abuse of Process in International Arbitration, 32(1) ICSID Rev. – FILJ 17, pp. 17-37.
[17] See also Aceris Law LLC, Document Production in International Arbitration, discussing the tribunal’s power to order document production and draw adverse inferences from unjustified refusal to produce documents.