The article deals with the role of national parliaments after entry into force of the Treaty of Lisbon, particularly with the early warning mechanism or so called yellow card. The author analyzes relevant provisions in primary law of the EU, especially Protocol on the Application of the Principles of Subsidiarity and Proportionality, where she points out disputable aspects of legal regulation.
Subsequently, the author summarizes experience with this institute a. Find deals with two cases of "yellow card" triggered by national parliaments regarding draft legislative acts of the European Commission.
Finally, de lege ferenda, amendments are introduced that might improve efficiency of the early warning mechanism.