Investor–State dispute settlement (ISDS) has been the preferred dispute resolution venue for redressing foreign investors’ investment grievances. As a result of its standing in adjudicating investment disputes, investment arbitration tribunals (investment tribunals) have increasingly been tasked with, for example, adjudicating at the crosshairs of international investment law (IIL) and environmental law.2 Thus, investment tribunals have indirectly been tasked with the great responsibility of regulating other regimes of international law—for example, international water services and international energy.