巴西共产党
In 1964, when the military instored their dictatorship, Pinheiro was admitted to Law School at the State University of Guanabara (currently UERJ). There, he joined the MR-8, then the most important urban guerrilla in Brazil, and connected to the Communist Party of Brazil. Again he was elected as chair of the student board ("Centro Acadêmico Luiz Carpenter").