The political economy of interest groups: pressure and information

We examine the incentives of an interest group to provide a political decision-maker with policy-relevant information and to exert pressure on her. Both activities are costly but may induce the lobby's preferred policy. Our paper provides an integrated analysis of both lobbying activities and leads to interesting insights into the behavior of the interest group. Moreover, we show how conclusions of models that take into account only one of these activities may change. Our main results say that the relationship between the pressure exerted and the amount of information transmitted is not monotonic, and that an increase in the amount of information that the lobby transmits may be socially harmful. This analysis has immediate implications for the current discussions in the United States and Europe concerning the reform of their respective rules of party and candidate financing.