What is legal validity? Lessons from soft law

The purpose of this article is to use the elusive phenomena of legal validity and soft law to illuminate each other. Three notions of legal validity are distinguished. Source validity and binding force (in a special technical sense) are internal legal notions that are used in legal argumentation. On the contrary, efficacy (also in a special technical sense) is an external notion, used in descriptive theories about law such as sociology of law or legal theory. Source validity is a characteristic of, amongst others, legal sources and something was validly made in this sense if it was made by a competent agent in accordance with the relevant procedure. A rule has binding force if this rule exists and generates legal consequences when applied. A rule is efficacious if its consequences are accepted by the relevant legal subjects, including officials.
With these three notions of legal validity in place, the focus of the argument shifts to the nature of soft law and how it combines with the three notions of legal validity. For a proper analysis of soft law three elements are required. First it is necessary to replace the traditional rule-based view of legal reasoning by a view in which reasons, rather than rules, take the central place. For this purpose a special logic for reasons, reason-based logic, is introduced into the argument. Second it is necessary to replace the view of legal justification according to which justification consists of an argument with the object of justification as its conclusion, by a view that emphasizes the dialogical nature of justification. For this purpose, a dialogical variant of reason-based logic is briefly explained. And third, the view of legal reasoning as a reconstruction of legal effects that exist independently has to be replaced by a constructivist view according to which legal consequences are determined by means of legal argumentation.
On the basis of these three changes of perspective, the definition of soft law as law that can less easily be used in legal argumentation becomes understandable. Moreover, the tools that have become available by the introduction of the three notions of validity, dialogical reason-based logic and constructivism make it possible to identify different reasons why legal rules may be soft: limited applicability, dubious binding force, frequent exceptions, and weak reasons for the rule consequences.