The aim of this paper is to build a formal modelling and analysis framework for democracy using the theory of discrete event systems (DESs). Democratic progress generally implies the increase of people who meet their economic interests or political rights. To model this basic principle of democracy, this paper models the behavior of democratic progress and regression using a finite state automaton, and adopts the control framework of DESs in which each agent (controller or person) makes a decision to achieve its own private objective. Specifically, each agent makes a decision to enable or disable the progress and regression events to meet its private objective at each state. The final decision on enabling/disabling the events is made using majority rule. Based on the democratic progress model, this paper obtains the conditions for the democracy system controlled by such agents to be progressive or regressive.