Constitutional Fact and Theory: A Response to Chief Judge Posner

In his James Madison Lecture on Constitutional Law, Chief Judge Richard Posner chides both professors and judges for devoting too much attention to constitutional theory and too little time to empiricism. Although I agree with Judge Posner’s endorsement of empiricism, I dispute the roles he assigns empiricism and theory. Social science matters when interpreting the Constitution, but not in the way Posner posits. Facts cannot replace constitutional theories, nor can they mechanically resolve questions posed by theory. Instead, empirical knowledge is most useful in unmasking the theoretical assumptions that undergird constitutional law, in focusing those theories, and in contributing to a multidimensional view of society that informs the substance of constitutional law. In this correspondence, I will examine the flaws in Judge Posner’s attempt to substitute empiricism for constitutional theory. I will then explore three more constructive roles that empiricism can play in constitutional law.