Abstract
Supreme Court of the french judiciary system, the Court of cassation has the mission to control the respect of the law ; the Court is its gardian. Its decisions are imperative upon the lower jurisdictions of the judicial system. This role of the High Jurisdiction is the inheritance of the revolutionary period during which the will was to ward off the government by judiciary. This government of judges took place in France under the Old Regime through the activity of Parliaments. Through this will of break was born a legalistic ideology : the activity of the judge is supervised by the law ; judges has to argue according to it. Considering this, the thesis adopts then a descriptive approach : the legalism has an impact on the conception of the judge, his judicial activity and its expression. The judge is presented as the mouth of the law. Nevertheless, behind this formal appearance, these brief motivations of the decisions and these syllogistic reasonings, the judge of the Court of cassation shows himself an interpreter and has a real normative judiciary power. This work suggests then revealing this reality, to explain how it becomes established and to understand why in spite of the obvious fact of the reality, the legalistic appearance remains the official representation. A gap between the appearance of the office of the judge as it is expressed and the reality of the office as it is exercised is thus identifiable. It’s on the basis of this observation and by considering the international constraints (european constraints in particular) impacting the judge activity that this thesis chooses to have a pragmatic approach by suggesting evolutions of the judicial function in an objective of coherence, intelligibility and efficiency of the justice.