Democratic deliberation has been shown to lead to shifts in people's preferences for particular issues. The psychological mechanisms that underpin such shifts are not well understood. Against the backdrop of a deliberative forum we examined participants' preferences for various types of political systems, how these preferences changed as deliberations proceeded and how the final preferences were associated with different levels of inclusiveness of a social identity. The results showed that at the end of the deliberations people's preferences moved in the direction of satisfaction with the political system, and that this preference was positively associated with identification with the superordinate identification but negatively associated with the subgroup identification. We discuss the implication of these results for the design of deliberative forums as well as the role of social identity in deliberative democracy. Author Biography Luisa Batalha is a social psychologist working at the Australian Catholic University. Her mains research interests are intergroup relation, the psychology of climate change mitigation and collective action. Simon Niemeyer is an Associate Professor and co-founder of the Centre for Deliberative Democracy and Global Governance. His research ties together the themes of political behaviour, the public sphere and observations from deliberative minipublics, such as Citizens' Juries, to develop insights into potential interventions and institutional settings that improve deliberation and governance. Johh S Dryzek is Centenary Professor at the University of Canberra, Australia. He works in both political theory and empirical social science. Dryzek is best known for his contributions in the areas of democratic theory and practice and environmental politics. One of the instigators of the 'deliberative turn' in democratic theory, he has published numerous books in this area with Oxford University Press, Cambridge University Press, and Polity Press. His work in environmental politics ranges from green political philosophy to studies of environmental discourses and movements to global climate governance, and he has published five books in this area with Oxford University Press, Cambridge University Press, and Basil Blackwell. John Gastil is Professor of Political Science at Penn State University. Gastil is widely credited for promoting deliberation among citizens during elections and in other political institutions. In his book By Popular Demand, he proposed creating panels of citizens, chosen randomly to ensure a cross-section of society, to deliberate on ballot initiatives and referenda.