Rationality, Legitimacy, & The Law

American legal realism was committed to examining legal reasoning in terms of the actual experiences of judges. Because the realist project sought to use social science tools to examine human nature, the contemporary rise of cognitive neuroscience provides an occasion for re-examining legal realism’s foundational critique of the law. Realism’s attempt to examine “the actual facts of judicial behavior” and to pursue a “scientific description and prediction of judicial behavior” appears to be a suitable vehicle for considering the relevance of cognitive neuroscience for legal theory. Cognitive neuroscience has provided convincing evidence for rejecting the traditional bifurcation between “reason” and “emotion”. Moreover, cognitive neuroscience has revealed key heuristic biases in human reasoning. As such, the dominant form of legal reasoning might rely on a flawed conception of rationality. And this flawed understanding may have implications for the legitimacy of judicial decisions. Rule-based reasoning has informed the image of rational adjudication that undergirds our conception of the rule of law. But rule- based reasoning does not appear to be a complete description of how judges decide cases; and, furthermore, the received view of legal rationality does not appear capable of accounting for alternative theories of adjudication.