Replacement naturalism and the limits of experimental jurisprudence

This essay is concerned with Brian Leiter’s so-called replacement naturalism, according to which the traditional methodology of conceptual jurisprudence ‘should be replaced by reliance on the best social scientific explanations of legal phenomena.’ I argue that, although the methodology of experimental jurisprudence is the only plausible replacement for the traditional methodology, it cannot can replace the philosophical methods traditionally used to address conceptual issues and, further, that experimental jurisprudence needs a theoretical foundation that properly locates its role relative to that of conceptual theorising and clarifies its methodology. To this end, I discuss three recent studies that attempt to ascertain the intuitions of competent speakers on three longstanding conceptual disputes about law: two attempt to show our folk concept of law is antipositivist, whereas the other attempts to show our folk concept of law is consistent with the existence of sanction-less legal systems. I argue that all three studies suffer from defects indicating the empirical methodology of experimental jurisprudence can supplement, but cannot replace, the traditional philosophical methodology for addressing conceptual questions. I argue, finally and far more worrisomely, that the last study calls into question its usefulness even in supplementing the traditional philosophical methodology.