By constituting the European System of Central Banks (ESCB), the member states in certain segments of their monetary sovereignty agreed to restrictions regarding the free creation and conduct of monetary policy. With the creation of the European Central Bank, national banks did not cease to exist, as some theoreticians point out, but their competence in the field of monetary and credit policy was certainly narrowed.

The ECB has the status of a legal entity, i.e. can be the holder of rights and obligations and conclude various types of contracts and other legal transactions dispose of movable and immovable property and have the status of a participant in court proceedings. the level of medium-term monetary goals, key interest rates, the level of mandatory reserves of national banks, and issuing guidelines for their implementation.

The European Central Bank initiates the monetary legislation of the Union and performs an advisory role related to the proposals of certain legal acts. In practice, the jurisdiction of the ECB was often modified by current economic conditions and often acquired new dimensions determined by acts of secondary legislation (which sometimes conflict with the provisions of primary law).

The competencies of the ECB are not definitively rounded, which is why it must be viewed realistically, outside of the current legal solutions, and shaped so that there is always enough room for maneuvering to acquire some new powers that are necessary for moments of crisis to stabilize the monetary system. The powers that the ECB has are not the result of the delegation of powers by the main EU institutions, but they are the result of the original powers established by the founding treaties. This is important to note because this is exactly what separates the ECB from the position of other decentralized agencies within the Union, which also have the status of a legal entity, but their powers are derived. The work of the Court of Justice is very important for the realization of the concept of independence of the ECB. A significant case from ECJ jurisprudence is the judgment in the case of OLAF, which decisively confirmed the independence of the ECB in all the mentioned dimensions. financial interests of the bank (Decision 1999/726/EC of 7 October 1999 on fraud prevention). In this dispute, the ECB highlighted the existence of an agreement that it concluded with the Commission to fight against contracts and actions harmful to its financial interests. That cooperation ultimately resulted in the adoption of the European regulation establishing the European Anti-Fraud Office (OLAF). This body represents the general service of the General Directorates of the Commission. Its task is to investigate all dealings harmful to the EU budget within the institutional structure of the Union in a manner that is accountable, transparent, and cost-effective.

OLAF does not have an executive or judicial function and is a hybrid expert body of the Commission, which is independent in conducting investigations and tasks but submits reports on its work to the Commission. The existence of a legal entity, its decision-making bodies, and capital, privileges in the work of the ECB with the possibility that only the ECJ decides on the dismissal of the members of the council of governors and the executive board, according to the understanding expressed in the judgment is a sufficient and necessary condition (confirmation) of the independence of the work of the supreme monetary institution of the EU. The European Court of Justice has explicitly taken the position that the ECB should act independently in carrying out entrusted tasks. The Court considers that Article 108 of the Maastricht Treaty represents a kind of "shelter" of the ECB from various political influences, for the sake of efficient realization of the tasks established by the provisions of the founding treaty and the statutes of the ESCB and the ECB. Certainly, we can note that the Court in this judgment talks about limited, not absolute independence because the ECB is independent within the community institutional structure, but not independent from the Community itself. Its independence is limited by the provisions of the primary and secondary law of the EU, namely the founding treaties and the Statute of the ECB. In this judgment, the Court expressly states that the work of the ECB is subject to responsibility control, primarily by the Court of First Instance, as the first instance, but also by the ECJ, as the (ultimate) second instance. Taking into account the concept of democratic legitimacy, according to which the power of all state-political institutions originates from the citizens and returns to them, a distinction can be made between the so-called input legitimacy (eng. input legitimacy), ie legitimacy by procedure and output legitimacy (eng. output legitimacy), ie legitimacy by results. The legitimacy of the procedure exists in the case when subjects make decisions based on the authority delegated by citizens, while the legitimacy of the results is assessed about the fact whether the elected representatives have fulfilled their expectations and needs. According to this theoretical position, the ECB enjoys the legitimacy of the procedure, which results from the delegation of part of the monetary sovereignty from the national to the supranational level of government. The way of appointing the members of the Executive Board and the General Council speaks in favor of this fact. The powers of the ECB in the area of the single monetary policy are limited by clear conditions and rules that confirm the form of procedural legitimacy. In certain circumstances, the ECB may have another form of legitimacy, if it bears responsibility for failures in achieving and maintaining price and financial stability.