Why and How: Public-Sphere Persuasion and Institutional Legitimacy

Abstract

Norms acquire institutional legitimacy when recognized as rationally justifiable. I develop a model of public-sphere persuasion in which individuals evaluate candidate norms along two dimensions, merit and implementability. Endorsement is bundle-based: a norm must be judged desirable and institutionally feasible. In Weberian culture---one expecting strict separation between technocratic administration and normative authority---state agents internalize a role conception providing them a cost advantage in implementability arguments and a handicap in merit ones, so peer and state-agent persuasion need not operate symmetrically. A second cultural margin is symmetric: both channels' persuasive effort depends on how far the prevailing grammar of legitimacy makes public justification consequential. I characterize the equilibrium persuasion architecture: when each channel bundles merit and implementability internally, peer and state-agent exposures are substitutes, while a positive interaction is possible only under cross-channel fit. I test the model using Swiss panel data on support for equal institutional treatment of in-group and out-group members, combining content-weighted exposure and workplace-switch designs. Both peer and state-agent exposure raise endorsement while their interaction is negative. Private-to-public non-mission switches raise endorsement by 10 percentage points. Where Weberian culture is stronger, proxied by state secularity support, the state-agent effect weakens and the interaction turns positive---a sign reversal possible only under cross-channel fit. Where culture favors self-legislation, proxied by exposure to French republican state-building, channels' own effects strengthen and the interaction deepens. Cultural change is an endogenous process of norm legitimation whose pace and direction reflect a persuasion architecture shaped by that same cultural environment.