It's very interesting to note that in contemporary political philosophy there is almost no room left for democratic decision making because in most theories that we're given, more or less everything is already decided at a constitutional level I mean think of  theory of justice, it's the theory of justice that decides the basic nature of a constitution so the role of members of a government is simply to interpret and apply the constitution so they can make the most efficient tax policies given the basic constitution, but no individual has the authority to  challenge that constitution and change it by democratic means.