 First, interpretivism says that the explanation of rights and obligations in which both moral principles and institutional practice play some role is a kind of interpretation.  Interpretation in the relevant sense is the study of normatively significant objects or of the actions of producing such objects and the practices within such production takes place. It is a familiar point from literary and other kinds of interpretation in the arts that an interpretation may impute to its object a certain content that consists in or reflects its normative significance or impact, without thereby imputing the content to the psychology of the agent who produced the object; it is also a familiar point that an interpretation’s success does not depend on such  endorsement. In the case of law, an interpretation so understood may correctly identify, say, the change in rights and obligations that obtained in virtue of some enactment, even though the enactment’s having that impact was not considered and endorsed, in some specified sense, by the enacting institution.