Racial and social quotas are a very controversial subject in Brazil. They were implemented by the government as an attempt to minimize the gap between students. That way, students who had their high school education entirely at public schools get quotas. Also, African and Indian descendants gain a small percentage of bonuses on their Vestibular. That is considered an affirmative action policy.
Court challenge
In August 2005, at Universidade Federal do Paraná, a student was granted by a federal court the right to be admitted at the university because she had a better score on the Vestibular than several other freshmen that took advantage of their quotas. In 2012 a law was approved that gave quotas to students who came from public schools. The federal universities (such as UFRJ, UNIFESP, UFPR, UFRGS...) will have to save half of the vacancies for those students. As state owernship,the University of São Paulo, doesn't have to do it for now.