In classical law, efficiency is a quality but it is not the only one and it does not sum up Law. Indeed, if we define effectiveness as the quality of a person or a thing, material or immaterial (such as a law or a judgment, for example) to produce the effect one is looking for, then it is better for the Law to be effective rather than not. Beyond this truism, Law, being a practical art, is particularly sensitive to this quality.
But Law is not reduced to that. It expresses values, virtues, symbols, social rules. It institutes human beings as persons. It wants to make these rules effective, but on the one hand it balances this concern with others and, on the other hand, it seeks to express the very nature of what it poses, for example the attribution of prerogatives, of rights for the benefit of a particular person, if necessary in a costly and ineffective manner (eg social rights or procedural guarantees).
Regulatory theories, often based on the economic analysis of law, consider law as a "tool", an instrument that must be the most flexible, the simplest and the most secure Possible to achieve a goal that economic theory draws: for example, effectively building competition or preventing banking crises.
The concern for the goal becomes the first, it becomes the center: efficiency becomes the center of Law, while the latter becomes teleological. Law is reduced to being an instrument. This instrumental conception, which can be supported but which does not correspond to the classical conception of Law because it breaks its conceptual autonomy, permeates the regulatory law, in particular because it was thought by economists more than by of lawyers.
The transformation is particularly strong in matter of repression. The legal system has traditionally constituted criminal law as an autonomous branch. The regulatory repressive rules today tend to be used to increase the effectiveness of the ordinary regulatory rules, whether they are themselves corporate law (governance), civil law or public law. In this, repressive punishment is only intended to render effective a rule which is external to it. This primary concern for efficiency removes the guarantees and increases repression, which is now at the heart of the regulatory systems, which, to be effective, cease to be national, while criminal law is synonymous with the state and the regalian.