Consultive bodies play a balancing and moderating role in constitutional democracies. Despite their supportive and auxiliary nature, several constitutions across Europe concede these bodies the status of constitutional organs. However, even if governments are bound to request an advisory opinion there has been a decline in the level of observance and compliance with their recommendations. Thanks to their technical expertise decision-makers are supported by unelected actors that enrich their decisions with extra-political input that may alter the final outcome. Nonetheless, consultive organs lack the majoritarian character that derives from elections and their legitimacy. The main questions are: What is the role that consultive bodies play in European constitutional democracies, especially on executive decision-makers? What impact may deviating from consultive opinions have on constitutional erosion and degradation?