Abstract
<p>Questions and Answers of the European Supervisory Authorities pursuant to Art. 16b of the ESA Regulation have an enormous factual relevance. However, it is unclear what the legal nature of these statements is and how the judge has to deal with them. This thesis attempts to clarify these questions in terms of legal methodology. Starting from the doctrine of argumentation, the existence of a duty to refer as well as a change in the burden of argumentation is explained and thus the legal source property is clarified. It is made clear that each executive pronouncement must be considered separately and that, within the framework of a moving system, elements must be gathered that can justify a duty to refer and a change in the burden of argumentation.</p>