Party-interest group ties: The resource exchange model revisited

We examine the existence and strength of organizational ties between parties and interest groups by innovating on classic resource exchange theory. First, we propose that the nature of interest groups’ policy orientation and their general organizational capacity primarily explain the presence of ties, that is, ties are less likely to materialize when groups lack ideological policy goals and have limited organizational capacity. Second, the size and types of resources on offer from both sides are what principally account for the strength of existing ties. We hypothesize that resources from both parties and interest groups are positively associated with institutionalized relationships, but also that resources are hierarchically ordered, that is, resources that are exclusive for the transaction are particularly important for ties at higher levels of institutionalization. Using data from a novel organizational survey of parties and interest groups in seven Western democracies, we find support for the hypotheses using an integrated design of analysis.