An unprecedented internal confrontation has erupted at Brazil's highest court, the *Supremo Tribunal Federal* (STF), after Justice Alexandre de Moraes requested an investigation into his colleague, Justice André Mendonça, accusing him of abuse of authority and interference in the **Banco Master scandal**. The conflict centers on a highly sensitive police report that revealed a private exchange of messages between Moraes and the arrested banker at the heart of a massive fraud investigation. In a move to contain the crisis, STF President Justice Edson Fachin removed the dispute from the controversial 'fake news' inquiry and gave the key parties five working days to provide clarifications, underscoring the severity of the institutional rupture at the apex of the Brazilian judiciary. [cite:3, cite:7, cite:8]