In this article, I draw on the specific case studies of the Xakriabá people and the Judicial District of Manga, and the Maxakali people and the Judicial District of Águas Formosas, both located in the Brazilian state of Minas Gerais. I examine how criminal justice officials apply dominant concepts of indigeneity in these regional contexts, showing how they arbitrarily construct and deploy the category of Indigenous person based on essentialist assumptions of indigeneity that ignore Indigenous peoples’ self-identification as such. This adds to scholarship on how indigeneity is institutionally conceived and applied within the justice system in ways that contrast with Indigenous notions of it and aim to deny Indigenous persons recognition in legal processes. By providing specific accounts of how Indigenous defendants are treated in the justice system and experience loss of rights, I consider the professional practices of state officials within the broader framework of Brazilian indigenist policies.