The role of the U.S. federal government in regulating economic and social interactions has grown exponentially since the establishment of Madisonian democracy in 1788. This has undermined one of the Founders’ key assumptions—that the role of the federal government would be small. The three-branch structure of government is inadequate to control the vastly increased opportunities for private interests to influence policy. The power of private interests is unbalanced; easily organized influencers have far more weight than large, poorly organized interests. This leads to policies that promote inequality. In addition, political decisions are dominated by the reliance of legislators and administrators on interest group information and resources. There is little incentive for policymakers to consider their impact on the “general welfare,” however measured. Also, there is little effective quality control of federal policies. The standard remedy for these imperfections is regulation of campaign financing and lobbying. Unfortunately, such regulation is constrained by First Amendment freedoms. I propose creation, within the Madisonian framework, of a fourth branch with the power to veto policies that reduce aggregate welfare and equality of means.