The Czech idea of the constitutional tribunal is closely associated with the concept of the constitutional court as a negative legislator. The idea goes back to the early 1920s, to the teaching of normativist school of law that influenced the creation of the first Czechoslovak Constitutional Court of 1920. The idea of the Court as a negative legislator is controlling nowadays as well; it has found its way into all major textbooks in the field.

In this report, I first outline the history of the constitutional courts on the Czech territory. I also explain the power held by the current Czech Constitutional Court. The second part describes constitutional complaints and their potential to modify the conception of the Court as negative legislator. Then I proceed with analyzing interpretative decisions in abstract constitutional review, which accounts for the situation when the Court does not annul the law but rather provides its interpretation, which is constitutional. The fourth and fifth sections deal with several types of cases in which the constitutional court serves as a real negative legislator. First, I analyze several positive aspects of decisions annulling laws. Then I discuss one of the most controversial issues – the constitutional court's lawmaking activity in the area of unconstitutional gaps in the legal order. In the sixth section, I raise the question of what happens to the text of the law if the last amendment to that law is annulled by the Court.