The current work, by means of the reconstructive method of approach, investigates recent performative alterations (2007-2008) of the Supremo Tribunal Federal (Supreme Court of Brazil) as signs of judicial activism. Thus, it carries through a bibliographical review of the concept of judicial activism in the scope of the constitutional jurisdictions, evidencing the semantic versatility of the expression, according to the model of constitutional jurisdiction that is adopted. Under the prism of a discursive theory of Law, the research considers criteria for the identification of judicial activism in the constitutional jurisdictions. Reconstructing an analytical system of concepts, it provides instruments to proceed to the analysis of recent speeches of the Supremo Tribunal Federal. At the conclusion of the analysis, the presence of the studied phenomenon is identified, with the criteria previously considered. Possible causes for the recent per formative alterations of the Court are, still, raised and, in summation, objections to the activist profile inaugurated by the Supreme Federal Court are pointed out.