This article asks why public officials perceive some interest groups as influential for policy outcomes. Theoretically, we rely on resource exchange and behavioral approaches. Perceived influence of interest groups does not only follow from the policy capacities they bring to the table; it also relates to the extent to which public officials consider groups as policy insiders. Both effects are assumed to be conditional on advocacy salience, i.e., the number of stakeholders mobilized in each legislative proposal. We rely on a new dataset of 103 prominent interest groups involved in 28 legislative proposals passed between 2015 and 2016 at the European Union level. Our findings show that interest groups associated with high analytical and political capacities are perceived as more influential for final policy outcomes than other groups with less policy capacities. Yet, in policy issues with high advocacy salience, interest groups characterized by higher ‘insiderness’ are perceived as more influential among public officials.

本文询问为什么公职人员认为某些利益集团对政策结果有影响力。理论上，我们依赖于资源交换和行为方法。利益集团的影响力不仅取决于他们提出的政策能力，还取决于他们的政策能力。它还涉及公职人员将群体视为政策内部人士的程度。假设这两种影响都取决于倡导的显着性，即每项立法提案中动员的利益相关者的数量。我们依赖于 2015 年至 2016 年间欧盟层面通过的 28 项立法提案所涉及的 103 个重要利益集团的新数据集。我们的研究结果表明，与政策能力较低的其他群体相比，具有较高分析和政治能力的利益群体被认为对最终政策结果更具影响力。然而，在具有高度倡导性的政策问题上，具有较高“内部性”特征的利益集团被认为在公职人员中更具影响力。