This paper aims to explain the extent to which the negotiators in trilogues deviate from the instructions they received from their institutions. Trilogue negotiations are modeled as consisting of two parallel principal-agent relationships as both the Council and the EP delegate the task to negotiate an interinstitutional compromise to an agent therein. The deal that these agents reach must be then approved by their respective institutions before it can be formally adopted as a legislative act. Hence, the process of negotiating inherently implies a tension between the need to deviate to reach a compromise and the need not to deviate too much for this compromise to be eventually accepted by both principals. In other words, delegation of authority in EU legislative policy-making requires deviation by the agents, but it puts limits on deviation too. This raises questions about how much do trilogue negotiators deviate from the instructions of the co-legislator they represent and how can variation in deviation be explained.
To address this issue, this paper measures the agents’ deviation through a new ‘deviation index’ that allows for a systematic measurement of the extent to which agent deviates from the mandate given by its principal. The paper then applies the index to the entire set of trilogue decision- making processes in the 2012-2016 period (N=111) to test several hypotheses based on the principal-agent model, through a multiple regressions analysis. This paper contributes to the literature on legislative policy making and early agreements in the EU as it allows identifying the conditions affecting deviation in trilogue negotiations. Moreover, it also contributes to the principal-agent literature by conducting a large-n assessment of agents’ behavior in the execution of their task. Whereas traditional principal-agent studies analyse deviation through qualitative case-studies, this paper aims to open a quantitative research venue in this field.
