Is the Court of Justice of the European Union a mere instrument in the hands of member states?

The thesis is an attempt to present the Court of Justice of the European Union as a rational actor performing in a strategic manner in accordance to its institutional preferences. The Court has been found to follow a self-perpetuating pattern of decision making that allows it to define a political agenda that the institution is aiming to achieve. This model is in line with the New Institutionalism theoretical assumptions and expectations and most especially to its rational choice and historical sub-branches. The findings in the dissertation are mostly in the quantitative analysis of an extensive dataset collected by the author for the research purposes of the project. The qualitative methodology is also used through the case study instrument of examining the doctrinal rulings from the Court‟s case-law and their relation to the „National versus communitarian‟ legal and political conflict and its often opposing interests. The key argument in the thesis is the finding that the Judges in their rulings at the Court of Justice seem to discriminate between the bigger countries and the rest of the less powerful EU member states. This enables the Court to balance between its institutional interests and those of the EU national governments which are a potential threat to the Court's pursuit of extended powers and competences, which is in agreement with all neoinstitutional arguments.