How To Measure Interest Group Influence: Evidence From Italy

The question of who wins or loses in the policy-making process lies at the very heart of recent research into both interest groups and public policy (Baumgertner et al. 2009; Klüver 2013). However, one of the most difficult challenges when empirically analyzing interest groups consists in knowing exactly how to measure their respective influence (Baumgartner and Leech 1998; Mahoney 2007; Beyers et al. 2008; Dür 2008; Lowery 2013): despite the fact that this question has been addressed by political scientists for decades (Truman 1951; Dahl 1961; Salisbury 1984; Verschuren e Arts 2004), significant problems remain regarding both the conceptual definition and empirical measurement of influence (Dür and De Bièvre 2007). In order to develop a better understanding of interest groups influence, I recommend as follows: a) that such influence be conceptualised as a degree of preference attainment (Schneider and Baltz 2003; Bernhagen 2012); b) that the degree of generality of the concept be downgraded, by breaking it up on the basis of two fundamental dimensions: the lobbying direction (pro-status quo or anti-status quo) and the policy-making stage (agenda-setting; decision-making; implementation); c) to proceed with a manual hand-coding in order to obtain a list of the policy issues around which interest groups lobby; d) to resort to an expert survey in order to evaluate – both qualitatively and quantitatively – these issues. Hence, it is possible to empirically measure interest groups’ influence if and only if: they are pro-status quo interest groups in the decision-making stage of the policy process; they face the same policy makers during the entire decision-making process; such a process is as brief as possible. This methodological approach is used to empirically measure the influence that Italy’s Professional Orders had on the liberalization process championed by the second Prodi Government in 2006.