This essay intends to cover the empirical aspects of the performance of the Federal Audit Court (Tribunal de Contas da União - TCU) since the beginning of the Constitution of 1988 to 2010. To this end, the work begins with a theoretical approach on the state accountability, represented by the accountability phenomenon, analyzed by several political scientists, especially in the context of Latin America. In a second moment, we pass to the study of the figure of the Audit Courts, summarizing the characteristics of some base models of external control agencies in other countries, writing, after that, about brief historical aspects of TCU - with emphasis on the debates of the 87-88 Constituent - and culminating in the regulatory and institutional aspects of the Federal Audit Court in Brazil. Finally, the work reveals the real features of the action of TCU, demonstrated by the legal successive internal comparison, carried out under two main guiding aspects related to the Court (the annual review of accounts rendered by the President and the exercise of some ordinary activities of TCU, such as inspections, receiving complaints, executive lawsuits, among others), covering the period from 1989 to 2010.