Life on the Legitimacy Frontier: Understanding the Authority Struggle Between the UN Security Council and the Office of the Ombudsperson

Since its creation in 2009, the UN Security Council’s Office of the Ombudsperson (OO), which reviews complaints by individuals listed as terror suspects in the so-called 1267-regime, has been locked in a protracted authority struggle with its principal. While the Council repeatedly sought to curtail the Ombudsperson’s autonomy—through restrictive mandates, poor working conditions, and delayed appointments—the eminent jurists heading the Office have learned to “fight back” through subtle institutional maneuvers, public reporting, and quiet diplomacy. Despite recurrent attempts at undermining it, the OO has become a surprisingly solid and effective corrective in the UN’s counterterrorism regime. This dynamic is puzzling: rather than a clear-cut case of principal control or agency slack, the UNSC–OO relationship unfolds as a tacit and iterative contest over authority. We argue that this pattern results from the mediation of the principal–agent relationship by external legitimacy audiences—notably courts and advocacy networks—that constrain the Council’s capacity for control while providing the OO with normative resources to resist. These audiences define the bounds of acceptable action, within which both actors navigate a precarious equilibrium – what we call the legitimacy frontier. Drawing on semi-structured elite interviews with Ombudspersons, UN officials, and state representatives, the paper traces this legitimacy-mediated struggle to theorize how IO authority evolves under normative constraint.