There is an article on the European Parliament (EP) website today (available here) examining the impact of the Lisbon Treaty on comitology. Until now the European Commission's implementation of much EU legislation was overseen by committees of Member State experts, through the so-called "comitology" system, which was criticized for its lack of transparency and democratic oversight. The Lisbon Treaty will replace comitology with "delegated acts," which come under parliamentary control.
With "delegated acts" the European Commission will be able to set out the technical requirements flowing from EU law, provided they don't affect the "core" legislation decided by Parliament and the Council. The delegation of power to the Commission will be subject to limits, conditions and controls. According to Article 290 of the Treaty on the Functioning of the European Union (TFEU),
"1. A legislative act may delegate to the Commission the power to adopt non-legislative acts of general application to supplement or amend certain non-essential elements of the legislative act. The objectives, content, scope and duration of the delegation of power shall be explicitly defined in the legislative acts. The essential elements of an area shall be reserved for the legislative act and accordingly shall not be the subject of a delegation of power.
2. Legislative acts shall explicitly lay down the conditions to which the delegation is subject; these conditions may be as follows:
(a) the European Parliament or the Council may decide to revoke the delegation;
(b) the delegated act may enter into force only if no objection has been expressed by the European Parliament or the Council within a period set by the legislative act.
For the purposes of (a) and (b), the European Parliament shall act by a majority of its component members, and the Council by a qualified majority.
3. The adjective "delegated" shall be inserted in the title of delegated acts."
The precise legal framework of the EP's role in delegated powers is still under discussion. On March 23, 2010, the EP's Legal Affairs Committee unanimously stated its position on how this delegation of powers should be carried out, the conditions and the limits, and ways to supervise the Commission's use of those powers. According to the MEPs, the goals, content, scope and duration of each case of delegation must be "expressly and meticulously" defined in each act (regulation, directive or decision). The ways to control the use of delegated powers by the Commission, the EP's right of objection and revocation, the duration and renewal of a delegation and a need for a Common Understanding between the institutions on certain practical arrangements are also some of the issues dealt with in the Legal Affairs Committee report (see the press release here). The report will be discussed in plenary this month.
The European Commission had already published, on December 9, 2009, an interesting Communication to the European Parliament and the Council on the implementation of Article 290 TFEU. The purpose of this Communication was to set out the Commission's views on the scope of the delegated acts, the framework for delegations of power, the working methods the Commission intends to use for preparing the adoption of delegated acts and, finally, the conditions under which the legislator might exercise control over the way the powers conferred on the Commission are implemented. I am attaching the full text of this document here [Communication on delegated legislation.pdf]
Additional background information on comitology and delegated acts (In Q&A form) is available here.