The thesis explores the metaethical foundations of value-based arguments in constitutional adjudication. The main argument develops in four steps. First, the thesis identifies three dominant types of value-based arguments in comparative constitutional practice: the argument from constitutional identity, the argument from common sentiments, and the argument from universal reason. Second, it brings to the fore the assumptions about the nature of moral value implicit in these arguments and subjects them to a critique. The thesis maintains that these arguments presuppose inadequate conceptions of value and fail as self-standing approaches to moral judgment. Third, the thesis develops an account of moral value and explains its practical consequences. It argues that a credible understanding of value suggests that the appropriate moral judgment emerges from the dynamics between practical confidence, which denotes the inescapability of the self and of the contingent evaluative attitudes it entails, and reflection, which denotes the process of challenging and questioning these attitudes. Fourth, departing from this conception of value, the thesis reconstructs the existing value-based arguments of constitutional courts. It applies the ethics of confidence and reflection to constitutional reasoning and shows how the arguments from constitutional identity, common sentiments and universal reason can be combined to refashion the moral perspective of a constitutional court so that it coheres with a sound understanding of value. The thesis argues that the moral inquiry of the constitutional court ought to depart from the emotive intuitions of the constitutional community and then challenge these intuitions through reflective exposure to different perspectives in order to better understand and develop the underlying constitutional identity. The thesis contends that this model enables us to perceive some common constitutional dilemmas in new light and allows us to move forward in resolving them.