This article intends to review, based on conceptual reference to necessary elementsrelated to the judicial decision as the constituent power, limits to the power of reformand substitution judgement of the Constitution, the arguments put forward by theConstitutional Court in order to justify its position regarding the unconstitutionalityof the reform indicated in the court verdict C-285 of 2016 because it replaces a fundamentalpillar of the Constitution, which is the principle of judicial self-government,the use of this principle as a basis for the decision adopted is problematic, since,on the one hand, it is not within the constitutional clause, while on the other, otherprinciples could be pointed out that would conflict with this and based on them theattempted reform would become constitutional.