Bargaining power in informal trilogues: Intra-institutional preference cohesion and inter-institutional bargaining success

Informal trilogue meetings are the main legislative bargaining forum in the European Union, yet their dynamics remain largely understudied in a quantitative context. This article builds on the assumption that the negotiating delegations of the European Parliament and the Council play a two-level game whereby these actors can use their intra-institutional constraint to extract inter-institutional bargaining success. Negotiators can credibly claim that their hands are tied if the members of their parent institutions hold similar preferences and do not accept alternative proposals or if their institution is divided and negotiators need to defend a fragile compromise. Employing a measure of document similarity (minimum edit distance) between an institution's negotiation mandate and the trilogue outcome to measure bargaining success, the analysis supports the hypothesis for the European Parliament, but not for the Council.