Institutional vs partisan interest: under what circumstances do rapporteurs in the European Parliament act in their group's interest in trilogue?

As the sole negotiators representing the European Parliament (EP) in interinstitutional negotiations, rapporteurs are endowed with an important responsibility. As the literature has demonstrated in the past, they do not always perform their duty to defend the EP’s mandate, and can instead choose to utilize their influence to shape outcomes in their favour. Using an original dataset containing the preferences of all of the EP’s groups on 30 legislative dossiers from the Ninth Parliament, we attempt to determine the conditions that allow rapporteurs to use their influence to benefit themselves. We test two types of moderators: structural factors (e.g. the committee responsible for the file, the capabilities of the shadows, the size of the majority in the EP, the salience of the dossier etc.), and personal factors (e.g. the group and nationality of the rapporteur, his/her level of experience etc.). Our article provides further contribution towards the understanding of the interplay between the important institutional roles that ultimately shape EU legislation.