Challenging investment-treaty arbitral awards in domestic courts on account of investor misconduct

In investment-treaty arbitrations, strong evidence of investor misconduct is like dynamite for States: it can destroy investors’ claims. For this reason, allegations of investor misconduct are frequently made in investment-treaty arbitrations. Most States, however, fire blanks with these attempts to blow up investors’ claims. Arbitral tribunals rarely side with States. But could they find more receptive audiences in domestic courts? This article investigates this question. After explaining the mechanics relating to how States can bring investor misconduct–grounded challenges against investment-treaty arbitral awards before domestic courts, it surveys the cases where States have filed such challenges. That survey catalogues their successes and failures, and details the jurisprudence that is emerging from those cases. Contrary to what States might hope, domestic courts are rarely receptive to their allegations of investor misconduct. And potentially more consequentially for States, they are developing jurisprudence that generally favours investors.