In the preparatory discussions and negotiations that led to the Maastricht Treaty, central banks took the view that monetary functions are indivisible and that, contrary to the fiscal field, subsidiarity cannot apply to the monetary field. Their traditional and strongly held position has been that the public interest assigned to central bank is a whole which cannot easily be decomposed. Indeed, while there is a fairly well developed theory of fiscal federalism, there is no equivalent for the monetary field.
On a functional ground, i.e. from the point of view of the relationship between economic variables that models usually consider, a chronically weak economy is one in which expectations deteriorate, investments stagnate, consumption declines. Structural unemployment may increase the risk of a deflationary spiral because a longer expected duration of unemployment may imply that households respond more conservatively (in terms of increasing savings) in the face of a deflationary shock. Today, we see no signs of deflation. Markets and observers who pay attention to communications by the Eurosystem know that the monetary policy strategy of the euro area is symmetrical, equally attentive to inflation and deflation. Thus, they know that if that risk became reality, the Eurosystem would have to act, and would act. But we know that monetary policy is much less effective in countering deflation than it is in countering inflation.
In the articulation of any federal constitution (Bund, Land and local, to use the German terminology) the central bank undoubtedly belongs to the level of the "federation", or Bund. The fact that important activities are conducted by "local" components of the system (Landeszentralbanken, or Federal Reserve District Banks) is an organisational feature that does not impinge upon the constitutional position of the central bank. The same happens within Monetary Union. The Eurosystem is the central bank of the euro area, even though operations are carried out - to the extent possible and appropriate - through its component parts, the NCBs. Indeed, the constitutional and the organisational profile of the institution are not in contradiction.
Although a federal and decentralised central bank is not a novelty, the Eurosystem is a special case. It is the central bank of an economy that has a much deeper national segmentation than any other currency area. Its components have for many generations (and until few weeks ago) performed the full range of central banking functions under their own responsibility and in a national context. They have been accountable to, and sometimes dependent on, national institutions. Public opinion has perceived, and still perceives, them as national entities. The notion of the public interest they were referring to was the notion of a national interest. Significant differences existed, and partly remain, in their tasks, organisations, statutes and cultures.
It would be an illusion, I think, to expect or pretend to have a full and satisfactory answer solely from legal interpretation. And it would be unfortunate if the Eurosystem were to fall into the trap of the narrowly legalistic approach that paralyses international organisations. The Eurosystem is not an international organisation, its model is not the Articles of Agreement of the IMF. Of course, the answer will have to comply with the Treaty, which provides useful guidance. However, the system is entrusted to decision-making bodies that are composed not of lawyers, but of central bankers. They carry the primary responsibility to manage the euro and are accountable for that responsibility. They have known for years what a central bank is and how vague the wordings of central bank statutes have historically been. Their touchstone can only be, in the end, the effectiveness in the accomplishment of the basic mission embodied in the triadic paradigm of central banking functions.
Secondly, the central banker should avoid mistakes. It may seem obvious, but he should never forget that independence does not mean infallibility and that the likely new environment will offer no forgiveness for mistakes. A mistake would be the attempt to provide a substitute for the lack of structural policies by providing unnecessary monetary stimulus: it is not because the right medicine is neither supplied by the pharmacist nor demanded by the patient that the wrong medicine becomes effective. Another mistake would be to give the impression that the central bank has a ceiling in mind for growth, rather than for inflation. On the contrary, the central bank should make it clear that any rate of non-inflationary growth is welcomed and would be accommodated, the higher the better.