Brian Leiter (University of Chicago) has posted Legal Positivism About the Artifact Law: A Retrospective Assessment (L. Burazin et al. (eds.), LAW AS ARTIFACT (Oxford University Press, 2017)) on SSRN. Here is the abstract:
This paper defends legal positivism against the backdrop of the assumption that law is an artifact, not a natural kind, and that it is an artifact whose nature does not depend on the intentions of a creator. I argue that even within the constraint imposed by the metaphysics of what law is, positivism satisfies the most important theoretical desiderata, including locating law within a naturalistic worldview.