A Simple Model of the Commercial Lobbying Industry

In this paper we present a model of the behavior of commercial lobbying firms (such as the so-called K-Street lobbyists of Washington, D.C.). In contrast to classical special interest groups, commercial lobbying firms represent a variety of clients and are not directly affected by policy outcomes. They are hired by citizens, or groups of citizens, to advocate on their behalf to policymakers. In our analysis we address two basic questions; why do commercial lobbying firms exist, and what are the implications of their existence for social welfare? We answer the first part of this question by proposing that commercial lobbying firms possess a verification technology that allows them to improve the quality of information concerning the social desirability of policy proposals. This gives policymakers the incentive to allocate their scarce time to lobbying firms. Essentially it is this access to policymakers that lobbying firms sell to their clients. To address the question of social welfare we construct a simple general equilibrium model that includes commercial lobbying firms, and compare the equilibrium obtained under market provision of lobbying services to the first best optimum. We find that the market level of lobbying services can be socially either too large or too small, and characterize when each will be the case.