The European Police Office (Europol) is the EU's agency in charge of internal security and police cooperation. The establishment of Europol was a part of a political project inserted in the reform process of European integration wherein the signing of the Treaty on European Union in Maastricht constituted a culminating point. Decision on Europol's objectives, tasks and functions taken by the Maastricht European Council was crucial for its constitution and further development. A reconstruction of activities with regard to the setting up of Europol, as presented in this study, seeks to identify an 'original sin' which precluded emergence of a Union-wide police service authorized to investigate serious crimes resulting from transnational organized criminal activities and terrorism.