Constitutional law and international and European Union law: what dictates the limits of the interaction between the legal systems

The Article deals with the interaction between constitutional law and international as well as European Union law, which is revealed in the jurisprudence of constitutional courts. Competition between constitutional law, on the one hand, and international and supranational law, on the other, is analysed, by examining to what extent this competition is inevitable and what degree of importance falls on the official constitutional doctrine formed by constitutional courts. The Article particularly focuses on the development of the doctrine formulated by the Constitutional Court of the Republic of Lithuania in relation to the interaction between the Constitution of the Republic of Lithuania and international and European Union law, as well as looks at the essential changes in this doctrine that emerged in the jurisprudence of recent years (2017–2019) and have significantly modified the boundaries of this interaction. A certain scope of interaction between constitutional and international law in the modern global world is inevitable; it often resembles a competition to determine which of sui generis competing areas of law is more important. In order for constitutional law to remain open to the influence of international law, it is important to define the limits of this influence, which should not be exceeded by international and supranational law. This is a complex task facing national constitutional law. By broadening the limits of their influence, international law and European Union law, due to their nature not infrequently, even though not directly, seek to dominate in respect of national law, inter alia, constitutional law. The provision on the primacy of the Constitution as supreme law in respect to the application of European Union law is followed by a number of constitutional courts in the European Union Member States. In the Lithuanian constitutional doctrine, European Union law has been regarded as a certain source of inspiration for interpreting the provisions of the Lithuanian Constitution, creating preconditions for avoiding controversial interpretation. In its ruling of 14 March 2006, the Constitutional Court formulated the constitutional doctrine according to which European Union law has primacy in applying it in cases where it competes with ordinary legislation rather than with the Constitution; this doctrinal provision has been repeated more than once in subsequent acts of the Constitutional Court. The doctrine on the non-competition of European Union law with the Constitution (rule of collision) has been, in principle, modified (reinterpreted) in the Constitutional Court decision of 20 December 2017, in which European Union law is already also treated as a source for the interpretation of the Constitution. This new doctrine has also provided the basis for the Constitutional Court’s ruling of 11 January 2019. The newly formulated constitutional doctrine has expanded the scope of the operation of European Union law. The Article underlines that this turn in the constitutional doctrine formulated by the Constitutional Court of Lithuania took place without properly arguing and without duly substantiating the necessity (inevitability) of neither such a new doctrine, nor its relationship with the constitutional concept of the Constitution as supreme law. Nevertheless, it is likely that the Constitutional Court will not deviate from the constitutional doctrine of the Constitution as supreme law, as this doctrine remains relevant and it will continue to provide the basis in the light of which the doctrine on the interpretation of the provisions of the Constitution will be developed, seeking compatibility between the two legal systems, without denying the principle of the supremacy of the Constitution