Inside the Portuguese Communist Party, Miranda was a member of the Central Committee and of the Regional Committee of Portalegre. In his last years, he left the Central Committee and became a member of the reformist group Renovação Comunista, which criticizes the Party's political orientation.
Tasks in the European Parliament
When Portugal joined the European Union, in 1986, the Communist Party included his name in the list of the Portuguese representatives in the European Parliament. In July of the next year, the first Portuguese European Parliament election was held and Miranda was among the three MEPs elected by the Unitary Democratic Coalition, where the Portuguese Communist Party was included. He continued to be elected in the subsequent elections, and was a member of the European Parliament until 2004, when he resigned due to health problems. There, Miranda was a vice-chairman of the European United Left–Nordic Green Leftgroup, and the chairman of the Committee on Development and Cooperation between 1999 and 2004.