The paper analyzes the factors that allowed the expansion of the Brazilian Supreme Court since 1988 compared to other branches of government, but also in a concentration of decision-making powers vis-à-vis other judges and courts. Institutional explanations prevail, which credit the strengthening of STF to the Brazilian Constitution. But, in this process, what is the role of STF´s justices? To answer this question, the research starts from Ran Hirsch's suggestion, which highlights the role of members of legal and judicial elites as a relevant part in the establishment of a juristocracy, in their claim to increase their power and/or gain international reputation. It supports the hypothesis that brazilian juristocracy is a product of the mobilization and articulation of STF´ justices in parliamentary processes – National Constituent Assembly and constitutional reforms – reinforced by jurisprudence that concentrates in the court the power to establish its own attributions ever since.