In this paper we examine the potential of democratic constitutions for the provision of divisible public goods in a large economy. Our main insights are as follows: When aggregate shocks are absent, the combination of the following rules yields first-best allocations: a supermajority rule, equal taxation, exemption of the agenda setter from taxation, and a ban on subsidies. In the presence of aggregate shocks to benefits or to costs of public-good provision, tax-sensitive majority rules, where the size of the required majority depends on the aggregate tax revenues, yield first-best allocations if a monotonicity condition is met. Finally, we explore the potential of first-best constitutions to induce voluntary participation by compensating agents belonging to the minority.