The negative and corrosive impacts of corruption in the fields of economics, politics, and law are widely discussed. Less understood are the potentially negative impacts of anti‐corruption struggles and strategies themselves. This article presents a case study of Brazil's ‘Car Wash’ (‘Lava Jato’) scandal from a legal and political perspective. Although the subsequent Operation Car Wash investigation was widely regarded as remarkably successful, supposedly buttressing the rule of law through high‐profile prosecutions of leading politicians and businesspersons, the article argues that legal due process, wider constitutional law, and the political process were undermined. While the use of media leaks to strengthen the investigation proved tactically successful, when coupled with new legal instruments it undermined the presumption of innocence and contributed to a climate in which political and legal debates themselves became increasingly subordinated to simplistic polarizing anti‐corruption discourses, thereby undermining an already fragile political and institutional environment.