The assignment of committee seats and reports reveals at the same time the political ambitions and reputations of Members of the European Parliament, as well as the strategic coordination efforts of (national) party (group) leaders. Thus, different types of MEPs contribute to different degrees and ways in co-constructing formal and informal authority structures within an rapidly evolving legislature. We advance a new theoretical perspective which highlights the dynamics of cumulative advantage in the field of legislative politics. For the first time, we investigate multiple memberships in EP committees connecting members and committees in a very complex, so far hidden way. Using network analysis, we identify latent structures of the organization in this parliament. Developing a new index of MEPs’ social capital, we are able to show that the multiplicity of committee assignments, but to a much higher degree the actual involvement (attendance) therein constitutes an intermediate investement leading to a higher chance of getting legislative reports. Conceiving highly prestigious reports as a ‘within-legislative-period-performance-indicator’ for important legislative action, we are able to determine the relative value of (specific) committee memberships.
