This study explores the relevance and application of the Utilitarianism principle in shaping public policy in Indonesia, with particular emphasis on the role of legislators in responding to demonstrations as expressions of public aspiration. The inquiry arises from developments in legal philosophy that question the status of law as a science and its relationship with morality and social utility, in line with the fundamental tenets of Utilitarianism. Drawing upon the philosophical foundations of Jeremy Bentham and John Stuart Mill, the principle of “the greatest happiness for the greatest number” serves as both a moral and rational basis for formulating policies directed toward the common good. Employing a normative legal-philosophical approach, this research examines how the utilitarian concept of utility is implemented within Indonesia’s legislative process and how it aligns with the values of Indonesian Positive Law, particularly in maintaining equilibrium between moral theory and the practical operation of law in society. The findings indicate that applying utilitarian principles in public policy requires the integration of both formal and substantive justice through laws that advance collective welfare. Legislators are expected to assess the social benefits of every policy objectively, transparently, and inclusively to prevent social disparity. Within the context of demonstrations, a utilitarian perspective interprets such public actions as indicators of social imbalance that should be addressed through policy reform rather than suppression of public expression. Overall, this study highlights the strategic significance of utilitarianism in reinforcing democratic legitimacy, legal morality, and the ultimate purpose of law—achieving happiness and public welfare for all citizens.