The rule of law principle is deeply rooted in the European legal tradition and is considered one of the key achievements of legal thought. Nowadays, it is difficult to imagine a legislator in Europe which would disregard this principle and shape the legal order without taking into account its rudimentary assumptions. Everywhere, as far as the eye can see, we observe normative acts either directly referring to the idea of the rule of law, or at least imbued with its spirit. Therefore, it is certainly a principle that is characterized by a universal character and a very wide range of influence.