In this article I analyze the challenges and contradictions involved in developing cultural expert witness reports to defend indigenous justice systems in contexts marked by violence and by the criminalization of organized indigenous movements. Through the analytical window provided by my experience as an expert witness in the defense of Nestora Salgado —leader of the community police organization in Olinalá, Guerrero, and a member of the regional system for indigenous justice Coordinadora Regional de Autoridades Comunitarias (Regional Coordinator of Community Authorities, or CRAC)— I would like to reflect upon the limitations as well as the possibilities of such reports in a context where the law has become an instrument of state violence and a means to justify the repression of autonomic indigenous projects.