This article studies the consequences of the increased appointment of political Commissioners for the legislative process. Based on the principal–agent relation between the Council and the Commission, it is hypothesized that governments sharing national and partisan ties with the Commissioner responsible for a legislative proposal are less likely to cast a negative vote. Analysing 687 contested legislative proposals voted upon between 1999 and 2014, it is found that a Member State is indeed less likely to vote against a proposal by the Commissioner from that Member State. Likewise, if the responsible Commissioner is a member of the same European Party Group as at least one of the governing parties, contestation is less likely. European Commissioners seem to use the discretion the EU's legislative system grants them to promote the preferences of their home country and also – to a lesser extent – their party family.