Informational lobbying in the European Union: Explaining information supply to the European Commission

Information supply is an important instrument through which interest groups can exert influence on political decisions. However, information supply to decision-makers varies extensively across interest groups. How can this be explained? Why do some interest groups provide more information than others? I argue that variation in information supply can largely be explained by organizational characteristics, more specifically the resources, the functional differentiation, the professionalization and the decentralization of interest groups. I test my theoretical expectations based on a large new dataset: Using multilevel modeling, I examine information supply to the European Commission across 56 policy issues and a wide range of interest groups by combining an analysis of consultation submissions with a survey conducted among interest groups.