  For hybrid interpretivism, the set of institutionally valid norms—the norms determined by what the institutions said—forms the interpretive baseline. Interpretation is a kind of moral processing of these norms. To interpret is to assess the norms constituted by institutional communication and adjust the set in order to make it more attractive in some way—to make it better conform to the abstract point of legal practice against which it is interpreted. Hybrid interpretivism is therefore the thesis that the institutional input to the interpretive process—what the institutions said—does not alone yield the final, complete set of legally valid norms. Rather, the final set of valid norms is the output of the process. The final set takes as an additional input certain moral facts. Yet the contribution of each kind of input remains distinct. Each episode of institutional communication, by itself, creates an institutionally valid norm which it makes available for interpretive scrutiny. The hybrid interpretivist considers as settled, without reference to any moral or other substantive normative facts, how the contingencies of institutional practice contribute to the law: he relies on the orthodox explanation of that mechanism (cf. Raz 1986, attributing the hybrid view to Dworkin). But he thinks that there are additional conditions of validity. Substantive normative facts may filter, supplement, or otherwise modify the original norms, as dictated by the interpretive goals in play. Legal validity of a norm now entails that the norm was either created by official communication and survived interpretive scrutiny or that it bears a certain relation, defined by the general point of legal practice, to such survivor norms.