In this article I argue that because of its emphasis on the use of reason, the Jafari Islamic school of thought is not only compatible with, but even promotes certain forms of deliberative democracy. I particularly focus on how this characteristic offers a valuable conceptual tool to promote peace and justice in deeply divided societies. My argument is grounded in traditional Shia theology and history but develops a political framework embedded within contemporary political theory. I distinguish this democratic political framework from the theocratic model of Wilayat-ul-Faqih, the political system currently being applied in Iran, and argue that an emphasis on rational argumentation opens a path towards reconciliation between Islamic principles and democracy. I analyse the potential benefits of deliberative democracy for Shias in both Middle Eastern societies and the West.