The authors contrast two political inquiries in light of Luhmann’s system theory of procedure. The article asks whether and to what extent these inquiries can be considered as procedural systems, meaning as distinct frames of action that generate specific meanings and relevancies. Starting from the micro-sociological analysis of interactions in the British “Hutton Inquiry” and the European Union’s “CIA Inquiry” the authors reconstruct the specific functionalities of each with regard to their different ways of engaging and enabling self-referential processes of communication, knowledge production, and decision-making. As a system, each merges these three processes into a consistent, relatively strong or weak procedure, but they do so to different degrees. Overall, the article encourages a sociological understanding of the procedural mechanism as well as an empirical qualification and variation of system-theoretical assertions.