The constraints of central bank independence: The European Central Bank's unconventional monetary policy and incremental accountability in the Euro crisis

Abstract

The European Central Bank (ECB) is one of the most independent central banks in the world, but this independence is also highly constrained: the Maastricht Treaty established a primary mandate to pursue price stability and prohibited it from engaging in monetary financing. Using an historical institutional framework, this article analyses the ECB's unconventional monetary policy during the Euro crisis. The Maastricht Treaty's constraints forced the ECB to act incrementally during the crisis and rely primarily on the layering of institutional changes. Nevertheless, the self-reinforcing effect identified by historical institutionalism meant that these gradual changes had important consequences over time. The unconventional monetary policies are contrasted with the more drastic institutional change instigated by the Member States, the ECB's designation as the Single Supervisory Mechanism (SSM). The self-reinforcing effects and path dependence set by the ECB's high degree of independence in the Maastricht Treaty, however, also constrained the EU in ensuring the accountability of the ECB, as the accountability structure is another instance of layering despite the very different nature and consequences of financial policy supervision.