These are all means by which attempts are made to draw the line between the competence of the Union to act and the competence of the member states. Of course, because the development of the EU is a dynamic process, the line is often blurred and disputes arise as to whether the member states or the Commission of the Union enjoy a competence and these have often been adjudicated by the CJEU. The Lisbon Treaty introduced a procedure (ART 12 TEU) to involve the national parliaments in determining whether a particular proposal should be undertaken by the Union or member states.2. What is the legal base of a Union law? Why is it important to know this and why have so many disputes arisen as to the proper legal base?
The legal base is the Treaty Article which empowers the institutions to enact secondary legislation and provides the details of which legislative procedure should be used, which in turn determines the role played by the law making bodies and whether, for example other bodies such as the Committee of the Regions should be consulted. The choice of legal base therefore is fundamental to the relative powers and ability of the institutions to affect the content of EU law and because different legal bases can be argued to apply to some subject matters, it may be that the Council uses one which does not give the EP its full say and the EP will dispute that.3. Why were there so many law making procedures?
The increase of the decision-making procedures is the product of a number of developments in the EU: the democratic deficit, the various expansions of member states, voting arrangements in the Council for the member states, movement and expansion of the EU into new policy areas, and as a response to the international regulation of pan European or even global problems such as the environment or business regulation. After a period of expansion, the Lisbon Treaty has now reigned these in by removing the original consultation procedure as a self standing procedure and abolishing entirely the co-operation procedure and by making the co-decision the predominant procedure in what is now designated the ordinary legislative procedure. This now is used to enact the vast majority (over 90%) of EU secondary legislation.