Conflict of Legal Bases and the Internal-External Security Nexus: AFSJ versus CFSP

Under the principle of conferral, the EU can act only within the limits of the competences conferred upon it to attain the objectives set out in the Treaties. Each Union measure must consequently be founded on a Treaty provision – the “legal basis” – that enables the Union to act in order to pursue a specific objective. EU Treaties provide for numerous legal bases, which relate to different policies and provide for different decision-making procedures. To determine the correct legal basis of a measure, one should apply the so-called “centre of gravity” doctrine, whereby the choice of the legal basis act must rest on objective factors amenable to judicial review, which include the aim and content of that measure. Yet, given the functional overlap between EU policies, it is sometimes difficult to identify the correct legal basis of a Union act. The selection of either an AFSJ or CFSP legal basis, in particular, may raise constitutional issues, in terms of the principles of conferral of competences and institutional balance. This paper analyses the ECJ case law on AFSJ/CFSP delimitation, distilling the elements that, according to the Court, may allow EU institutions to properly identify the legal bases of security-related acts. The analysis also elucidates the pitfalls in the reasoning of the Court, and suggests alternative solutions that might increase legal clarity.