This chapter explores the politics of EU law in the specific policy area of ‘freedom, security and justice’ (AFSJ). The chapter discusses several interrelated themes such as the development of EU criminal law cooperation, mutual recognition and the idea of trust as well as challenges to the rule of law. In addition, the chapter looks at the flexibility mechanisms and highlights how the boundaries of integration and disintegration has a clear political dimension to it when applied to the AFSJ. Moreover, the implications of a proportionality test in AFSJ matters is interesting as a manifestation of the intersection of law and politics. These themes and related questions will be considered in the present chapter.