The parliamentary scrutiny of European affairs takes a unique form in every Member State, reflecting domestic habits and constitutional traditions of the State. The choice of the model of involving the national parliament in discussing European matters is, therefore, an exclusively national issue. In general, Member States can be divided into those with a strong influence of the parliament on the attitude of the government, and those where that influence is weaker.
At the level of the European Union, the role of national parliaments in designing the European law was first addressed in the Treaty of Maastricht. Its Declaration (No 13) on the role of national parliaments called on governments to “ensure, inter alia, that national Parliaments receive Commission proposals for legislation in good time for information or possible examination”. The subsequent Treaty of Amsterdam already contained Protocol on the Role of National Parliaments in the European Union, establishing basic rules for informing national parliaments about EU affairs, including rules for delivering legislative proposals. The Protocol also envisaged interparliamentary cooperation of national parliaments. It emphasised that the scrutiny of governments by their national parliaments as regards the activity of the Union is a matter of the constitutional arrangement and practice of each Member State.
The role of national parliaments was further strengthened by the Treaty of Lisbon, enabling the national parliaments to participate in Union affairs in several areas. The most significant of them was the role of national parliaments as defenders of the subsidiarity principle in the EU legislative process as regards areas that do not fall within the exclusive competence of the Union. Based on the Protocol (No 2) on the application of the principles of subsidiarity and proportionality, the national parliaments or their chambers have eight weeks, starting on the day of transmitting a legislative proposal in all official languages of the Union, for adopting a so-called reasoned opinion stating non-compliance of the draft legislative act with the principle of subsidiarity. If the number of such reasoned opinions reaches a set quorum, the draft must be either reviewed (“yellow card”), or it may be even rejected by the Council or the European Parliament (“orange card”).
In addition, the Treaty of Lisbon inserted into the Treaty on European Union a new Article 12 that, for the first time, explicitly established the role of national parliaments in actively contributing to the good functioning of the Union. Apart from the subsidiarity scrutiny, it includes the right to be informed by the Union institutions and the right to receive drafts of Union legislative acts, participating in revisions of the EU Treaties and being involved in the political monitoring of Europol and in evaluation of Eurojust’s activities. National parliaments also “actively contribute to the good functioning of the Union” by participating in interparliamentary cooperation between the European Parliament and national parliaments, either through permanent bodies such as the Conference of Parliamentary Committees for Union Affairs (COSAC) or various ad hoc meetings.