The previous chapters have exposed the gap between the normative view of the role of a defence lawyer at the investigative stage (as implied in European laws) and the practical reality of legal assistance at this stage. This and the following chapters, in turn, aim at identifying some of the factors which are likely to shape or influence the respective practices, and which partly explain the origins of this gap. The influence of national legal cultures and legal (procedural) traditions emerges as the most obvious factor, which might explain the gap between the European normative view on the role of the lawyer at the investigative stage and the respective practice. Resistance from the procedural tradition was cited as the reason why certain national legal systems were reluctant to implement the broad right to custodial assistance (Brants, 2016). Thus, this chapter hypothesises that the practices of legal assistance at the investigative stage described in Chapters 3 and 4, which did not correspond to the normative view presented in Chapter 2, developed mainly on the basis of the prevailing procedural traditions, or (national) laws and regulations (understood broadly, i.e. inclusive of case law and rules of professional ethics), reflecting these ideas.