The expressive function of public policy: renewable energy mandates signal social norms.

Addressing collective action problems requires individuals to engage in coordinated and cooperative behaviours. Existing research suggests that individuals' propensity to work together depends in part on their belief that others support the cause in question. People form their expectations about prevalent beliefs and behaviours from many sources. To date, most of the literature has focussed on how social norm perceptions are inferred from peers or summary statistics. We explore an understudied source of norm information: the passage of policies by democratically elected institutions. Institutional signals, such as the setting of defaults, national laws or policies, can act as coordination devices, signalling or prescribing social norms to large audiences. However, their expressive function is likely to depend on whether the institution is seen as accountable to the public. In two highly powered, pre-registered experiments ( = 11 636), we examine the role of policy signals as a source of social norm information. In Study 1, Americans randomly assigned to learn that their state passed a 100% renewable energy mandate believe that a greater percentage of their state's residents support such a mandate. In Study 2, we replicate this effect for national policy and show that the influence is moderated by information about whether the government represents the will of the people. This article is part of the theme issue 'Social norm change: drivers and consequences'.