Norms, legitimacy and institutional independence: the active role of the European Court of Auditors in setting international standards

The European Court of Auditors (ECA), established in 1977, is the external auditor of the EU budget. It was given full EU institutional status in 1993. The Treaty of Amsterdam reaffirmed its independence and extended its audit powers. Based in Luxembourg, it employs around 900 people, of whom less than half are auditors. The ECA is meant to carry out its audit tasks 'in liaison with' the supreme audit institutions (SAIs) at the national level, each cooperating 'in a spirit of trust while maintaining their independence' (TFEU Art 287(3)). Through its work, it shapes and adopts new audit standards that guide its practice. It is member of International Organisation of Supreme Audit Institutions (INTOSAI) (1953), a forum that brings together professional and technical experts worldwide through working groups and task forces. Drawing on Oliver Buntrock's notion of 'micro-institutionalization', this article examines how and why the ECA formally engages in standard-setting at the international level. Drawing on primary documents and interviews, it analyses socialization processes and considers motives for participation. The article argues that membership of INTOSAI has helped bolster the ECA's professional and technical legitimacy over 20 years, and reinforced its independence vis-a-vis its main stakeholders, the European Parliament and European Commission. The paper contributes to our understanding of how a lesser-known EU body contributes to the evaluation of EU budgetary spending.