Theoretical and Practical DSL
As we saw before, the theories are tools for systematising norms (formulating and reformulating a system), and as such they belong to the level of theoretical DSL In this sense, theories, and especially them, serve the economy of thinking in providing an internally cohesive way to describe a certain set of legal provisions in a general form.
From this point of view, the change of the doctrinal study of law seems to concentrate on the transition from theory T1 to theory T2. Let us now have a closer look at this hypothesis (Poyhonen 111).The theoretical part of DSL deals with the systemic connections between norms and concepts, whereas the function of the practical part of DSL concerns the interpretation of the statutes, and that of the other legal source material. The practical part of DSL introduces information and/or recommendations as far as the content of legal order is concerned. In this regard, the practical part of DSL is always interpretative as to its nature.
The theoretical and the practical parts of DSL are in constant interplay with each other. Every legal interpretation is produced inside a certain theoretical (conceptual) framework. This, in its turn, is formulated by the theoretical DSL. In a puzzle case, where the conceptual frame cannot give support to an acceptable interpretation, there is a need to more closely redefine the necessary conceptual background. This is a typical case in the phase of normal science. On the other hand, a new conceptual framework normally gives rise to a new set of practical interpretations. That is what is meant by the term “interplay”.
The norms covered by the theory might be numerous, inaccurate by expression or contradictory, thus giving rise to what Alchourron and Bulygin refer to as a gap in knowledge. In some cases, the norms might be strained by a normative gap - that is, the system does not contain a valid legal norm at all as regards the problem at issue.
As far as the elimination of contradiction is concerned, it must be taken into account that the system of norms cannot in itself necessarily be contradictory, as has been convincingly shown by Georg Henrik von Wright (von Wright 1985,263). The question may also be about two (or more) mutually contradictory systems, and the elimination of contradiction thus always means selecting a certain system of norms and rejecting another.An interpretation using the theories formulated by the theoretical DSL strives to specify inaccuracies, block the normative gaps and eliminate contradictions. This is where the law-creating, or constitutive nature of DSL becomes clear. The same phenomenon has been characterised from the perspective of judges in Richterrecht - that is, the law created by the judges. DSL performs the same task as judges by presenting reasoned interpretative recommendations, even though these recommendations do not, of course, have the same normative status as legal decisions. They are only permitted sources of law.