We talk about “discretion of the judge” every time a Court is recognized the cognitive duty and the power to decide an appropriate sentence in accordance with the purposes of criminal punishment defined by the Parliament. This broad definition includes the power of the criminal courts to apply those that, in Italy, are called "misure di sicurezza". This paper traces the steps followed by the Constitutional Court to remove the presumptions and automatisms that characterize the original structure of the “misure di sicurezza personali”. It will mention the issues raised by the D.L. n. 52/2014, with which the Parliament sought to put an end to the so-called “ergastoli bianchi”, as well as the question of the Court’s power to determine the amount of a confiscation order, a measure that was born as a “misura di sicurezza patrimoniale” but, today, has become a proper criminal punishment. The paper intends to show that, even in the context of the “misure di sicurezza”, the Parliament has the tendency to limit (or eliminate) the discretion of the Court. This trend is not in accordance with the purposes of the instrument “misure di sicurezza” nor with the Constitutional principles.