Legal Positivism and Evolutionary Psychology: Can Legal Positivists Learn Something from Darwin?

Abstract

In the present essay, I consider the relevance of Evolutionary Psychology (EP) for legal positivism, addressing the two main traditions in the legal positivist family: (1) The tradition I identify with the works of H.L.A. Hart and Hans Kelsen and characterize as “normativist,” as it tries to describe law as a purely or, at least, as an essentially normative phenomenon while remaining true to the ideal of scientific objectivity and value-neutrality. (2) The tradition I broadly refer to as “legal realism,” which equates law with adjudication and “legal science” with the task of explaining judicial behaviour. On the assumption that the claims of EP are correct, I try to establish whether EP could and should inform the legal theories that have developed within these two traditions. My conclusions warrant a degree of scepticism, although I am somewhat less sceptical about possible interconnections between EP and the legal realist approach than I am about the Hartian-Kelsenian brand of legal positivism. What motivates my scepticism is the nature of the normativist enterprise, how normativists construct their theories and delineate their subject-matter. The truth is EP has little to say about the questions that are of interest to legal positivists of that persuasion. The situation is slightly different for the legal realist tradition and the theories that try to study judicial behaviour in causal terms. The question, however, is whether EP can help generate new testable hypotheses about judicial decision-making.