The aim of this paper is to explore the limits of the constraint satisfaction theory of coherence (CsCS) as a basis for a model of legal argumentation concerning questions about norms. The main thesis defended here is that CaCS is a promising basis for such model, but it has to overcome certain important objections. This paper focuses on objections of a technical nature, related to the problems of representation of arguments and relations between arguments in the framework of CaCS. The paper outlines possible ways of dealing with these difficulties and indicates a perspective of further research on the subject.