This dissertation analyzes the interaction of three regulatory bodies that monitor and penalize the activities of Brazilian companies: the Public Prosecutor s Office, CADE, and CVM. The benchmark of this analysis is the Car Wash Operation, led by the Public Prosecutor s Office, which indicted large corporations, mainly for corruption-related activities. Before, during, and after the Car Wash Opera tion, CADE and CVM remained active. These two regulatory bodies indicted companies for anti-competitive practices (CADE) and for actions harmful to minority shareholders (CVM). The broader temporal scope of CADE and CVM indictments allows us to estimate how punitive the indictments from these two bodies are, compared to the expected penalties associated with Car Wash in dictments. One hypothesis is that the rigor of Car Wash stimulated CADE and CVM to increase their monitoring and punishment efforts. Another hypothesis is that the pressure from the Public Prosecutor s Office softened CADE and CVM s monitoring. This dissertation finds evidence in favor of the second hypothesis, using event study methodology. Estimates of cumulative abnormal returns suggest that CADE and CVM indictments were more costly for the indicted companies outside the peak period of Car Wash. A possible reason for the lower impact of CADE and CVM indictments on stock returns could be that investors focused primarily on the Car Wash Operation. This focus might have led to inattention towards CADE and CVM indictments. However, event studies conducted in this dissertation dismiss this hypothesis. The data suggest that the reduced impact of CADE and CVM indictments during Car Wash was due to a lower effectiveness of these regulatory bodies.