When the inertia of Parliament results in a legislative gap with respect to fundamental rights enshrined in the Constitution, one wonders whether the ‘Judge of the Laws’ in contemporary liberal democracies can fill that lacune in order to ensure an effective fulfilment of the Higher Law. In the absence of clear ad hoc rules, several legal systems witnessed the creation of mechanisms to rebuild constitutional rights in its fullest extent through different manoeuvres of procedural engineering performed by Courts. To what extent can constitutional courts use their powers to fix Legislatures’ omissions? Can this behaviour be considered judicial activism? Does it erode constitutionalism’s principles? As examples of transformative constitutionalism, German and Italian constitutional justice systems will be compared to try to find provisional answers to the above mentioned questions.