The Making of Pan-European Infrastructure: From the Schengen Information System to the European Arrest Warrant

This chapter investigates how a complex EU criminal justice procedure, the European Arrest Warrant (EAW), has been implemented and is performing its function through the support of a pre-existing information infrastructure: the Schengen Information System (SIS). Below the apparently seamless surface of the enabling information infrastructure lays a world of complexity. The infrastructure supports the transmission of data as well as sensemaking and the solution of se-mantic, administrative and procedural micro-issues through its human 'intelligent' components operating in ad hoc organisational units. Complexity is embedded in the heterogeneous, loosely integrated, and time bounded components of SIS. The chapter also investigates how the attempt to introduce a more complete Schengen Information System (SIS II) in order to fully satisfy EAW requirements resulted in a never-ending normative and technological development phase. Building on this wealth of experience, the chapter provides an in-depth view of the dynamics affecting the development of large transborder information infrastructures support-ing the circulation of legal agency.