Conceptualizing and Measuring Party-Interest Group Relationships

It is widely assumed that the relationship between parties and interest groups shape the nature of democratic governance, with increasing attention paid to the intersection between party and interest group politics. Individual parties and interest groups are often described as being «aligned», «interlinked», «tied» and «connected» as organizations, but what this means in practice is unclear and contested. This paper contributes to conceptual and methodological debate by first summarizing how party-interest group relationships have usually been portrayed, both historically and more recently. Second, we conceptualize the relationship between parties and interest groups in terms of interaction. What attributes are constitutive of “party-interest group relationships”? Particular attention is paid to the distinction between the structured interactions that create enduring relationships, and the issue-based contact that is often central to studies of interest group behaviour. We make the case for studying the strength of structured relational ties, defined as those means by which a party and an interest group may interact repeatedly, generally and in specific areas. Third, we examine how we can form measures linking the relevant conceptual attributes with empirical observation. In the fourth part of the paper, we explore these issues empirically through an analysis of a novel dataset generated by the PAIRDEM project from a variety of sources, including questionnaires to key informants in both parties and interest groups in multiple countries. We examine the dimensionality empirically by means of a scaling analysis to find out whether the most institutionalized (formal) ties preclude – or even render superfluous – ties at lower (less formal) level or whether they instead nurture more ties. Based on these results, we calculate one or more aggregate scores. Thereafter, we examine the association between these general measures and more specific contact routines in different types of party decisions and policy fields. Finally, we compare the PAIRDEM data with other relevant data sets in the field. In this way, we systematically evaluate different indices used to study interaction between parties and interest groups.